From 3020026abfff8e6ff5fd3171ec3e490a570f1cf3 Mon Sep 17 00:00:00 2001
From: hskwon <shine1324@gmail.com>
Date: Fri, 19 Dec 2025 14:52:53 +0900
Subject: [PATCH] =?UTF-8?q?feat:=20Phase=205=20API=20=EA=B0=9C=EB=B0=9C=20?=
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 =?UTF-8?q?=EC=A0=95=EA=B4=80=EB=A6=AC,=20=EA=B1=B0=EB=9E=98=EB=AA=85?=
 =?UTF-8?q?=EC=84=B8=EC=84=9C)?=
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

5.1 사용자 초대 기능:
- UserInvitation 마이그레이션, 모델, 서비스, 컨트롤러, Swagger
- 초대 발송/수락/취소/재발송 API

5.2 알림설정 확장:
- NotificationSetting 마이그레이션, 모델, 서비스, 컨트롤러, Swagger
- 채널별/유형별 알림 설정 관리

5.3 계정정보 수정 API:
- 회원탈퇴, 사용중지, 약관동의 관리
- AccountService, AccountController, Swagger

5.4 매출 거래명세서 API:
- 거래명세서 조회/발행/이메일발송
- SaleService 확장, Swagger 문서화
---
 app/Console/Commands/FcmTestCommand.php       |   2 +-
 .../Controllers/Api/V1/AccountController.php  |  61 ++++
 .../Api/V1/NotificationSettingController.php  |  50 +++
 .../Api/V1/PushNotificationController.php     |   2 +-
 .../Controllers/Api/V1/SaleController.php     |  31 ++
 .../Api/V1/UserInvitationController.php       |  73 ++++
 .../Account/UpdateAgreementsRequest.php       |  36 ++
 app/Http/Requests/Account/WithdrawRequest.php |  32 ++
 .../BulkUpdateSettingRequest.php              |  39 +++
 .../UpdateSettingRequest.php                  |  36 ++
 .../AcceptInvitationRequest.php               |  32 ++
 .../UserInvitation/InviteUserRequest.php      |  32 ++
 .../UserInvitation/ListInvitationRequest.php  |  25 ++
 .../Requests/V1/Sale/SendStatementRequest.php |  16 +
 app/Models/NotificationSetting.php            | 226 +++++++++++++
 app/Models/UserInvitation.php                 | 176 ++++++++++
 app/Services/AccountService.php               | 240 ++++++++++++++
 app/Services/NotificationSettingService.php   | 180 ++++++++++
 app/Services/SaleService.php                  | 151 +++++++++
 app/Services/UserInvitationService.php        | 230 +++++++++++++
 app/Swagger/v1/AccountApi.php                 | 214 ++++++++++++
 app/Swagger/v1/InternalApi.php                |   3 +-
 app/Swagger/v1/NotificationSettingApi.php     | 173 ++++++++++
 app/Swagger/v1/SaleApi.php                    | 180 ++++++++++
 app/Swagger/v1/UserInvitationApi.php          | 311 ++++++++++++++++++
 ...00_create_admin_api_deprecations_table.php |   2 +-
 ...9_100001_create_user_invitations_table.php |  41 +++
 ...002_create_notification_settings_table.php |  47 +++
 lang/ko/error.php                             |  35 ++
 lang/ko/message.php                           |  30 ++
 routes/api.php                                |  37 ++-
 31 files changed, 2735 insertions(+), 8 deletions(-)
 create mode 100644 app/Http/Controllers/Api/V1/AccountController.php
 create mode 100644 app/Http/Controllers/Api/V1/NotificationSettingController.php
 create mode 100644 app/Http/Controllers/Api/V1/UserInvitationController.php
 create mode 100644 app/Http/Requests/Account/UpdateAgreementsRequest.php
 create mode 100644 app/Http/Requests/Account/WithdrawRequest.php
 create mode 100644 app/Http/Requests/NotificationSetting/BulkUpdateSettingRequest.php
 create mode 100644 app/Http/Requests/NotificationSetting/UpdateSettingRequest.php
 create mode 100644 app/Http/Requests/UserInvitation/AcceptInvitationRequest.php
 create mode 100644 app/Http/Requests/UserInvitation/InviteUserRequest.php
 create mode 100644 app/Http/Requests/UserInvitation/ListInvitationRequest.php
 create mode 100644 app/Http/Requests/V1/Sale/SendStatementRequest.php
 create mode 100644 app/Models/NotificationSetting.php
 create mode 100644 app/Models/UserInvitation.php
 create mode 100644 app/Services/AccountService.php
 create mode 100644 app/Services/NotificationSettingService.php
 create mode 100644 app/Services/UserInvitationService.php
 create mode 100644 app/Swagger/v1/AccountApi.php
 create mode 100644 app/Swagger/v1/NotificationSettingApi.php
 create mode 100644 app/Swagger/v1/UserInvitationApi.php
 create mode 100644 database/migrations/2025_12_19_100001_create_user_invitations_table.php
 create mode 100644 database/migrations/2025_12_19_100002_create_notification_settings_table.php

diff --git a/app/Console/Commands/FcmTestCommand.php b/app/Console/Commands/FcmTestCommand.php
index 296aa1a..c8ae248 100644
--- a/app/Console/Commands/FcmTestCommand.php
+++ b/app/Console/Commands/FcmTestCommand.php
@@ -131,4 +131,4 @@ public function handle(): int
 
         return self::SUCCESS;
     }
-}
\ No newline at end of file
+}
diff --git a/app/Http/Controllers/Api/V1/AccountController.php b/app/Http/Controllers/Api/V1/AccountController.php
new file mode 100644
index 0000000..b825d11
--- /dev/null
+++ b/app/Http/Controllers/Api/V1/AccountController.php
@@ -0,0 +1,61 @@
+<?php
+
+namespace App\Http\Controllers\Api\V1;
+
+use App\Helpers\ApiResponse;
+use App\Http\Controllers\Controller;
+use App\Http\Requests\Account\UpdateAgreementsRequest;
+use App\Http\Requests\Account\WithdrawRequest;
+use App\Services\AccountService;
+use Illuminate\Http\JsonResponse;
+
+class AccountController extends Controller
+{
+    public function __construct(
+        private readonly AccountService $service
+    ) {}
+
+    /**
+     * 회원 탈퇴 (SAM 완전 탈퇴)
+     */
+    public function withdraw(WithdrawRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->withdraw($request->validated()),
+            __('message.account.withdrawn')
+        );
+    }
+
+    /**
+     * 사용 중지 (특정 테넌트에서만 탈퇴)
+     */
+    public function suspend(): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->suspend(),
+            __('message.account.suspended')
+        );
+    }
+
+    /**
+     * 약관 동의 정보 조회
+     */
+    public function getAgreements(): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->getAgreements(),
+            __('message.fetched')
+        );
+    }
+
+    /**
+     * 약관 동의 정보 수정
+     */
+    public function updateAgreements(UpdateAgreementsRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->updateAgreements($request->validated()),
+            __('message.updated')
+        );
+    }
+}
diff --git a/app/Http/Controllers/Api/V1/NotificationSettingController.php b/app/Http/Controllers/Api/V1/NotificationSettingController.php
new file mode 100644
index 0000000..8f7873c
--- /dev/null
+++ b/app/Http/Controllers/Api/V1/NotificationSettingController.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace App\Http\Controllers\Api\V1;
+
+use App\Helpers\ApiResponse;
+use App\Http\Controllers\Controller;
+use App\Http\Requests\NotificationSetting\BulkUpdateSettingRequest;
+use App\Http\Requests\NotificationSetting\UpdateSettingRequest;
+use App\Services\NotificationSettingService;
+use Illuminate\Http\JsonResponse;
+
+class NotificationSettingController extends Controller
+{
+    public function __construct(
+        private readonly NotificationSettingService $service
+    ) {}
+
+    /**
+     * 알림 설정 조회
+     */
+    public function index(): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->getSettings(),
+            __('message.fetched')
+        );
+    }
+
+    /**
+     * 알림 설정 업데이트 (단일)
+     */
+    public function update(UpdateSettingRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->updateSetting($request->validated()),
+            __('message.updated')
+        );
+    }
+
+    /**
+     * 알림 설정 일괄 업데이트
+     */
+    public function bulkUpdate(BulkUpdateSettingRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->bulkUpdateSettings($request->validated()['settings']),
+            __('message.bulk_upsert')
+        );
+    }
+}
diff --git a/app/Http/Controllers/Api/V1/PushNotificationController.php b/app/Http/Controllers/Api/V1/PushNotificationController.php
index f461e2e..8f71413 100644
--- a/app/Http/Controllers/Api/V1/PushNotificationController.php
+++ b/app/Http/Controllers/Api/V1/PushNotificationController.php
@@ -2,11 +2,11 @@
 
 namespace App\Http\Controllers\Api\V1;
 
+use App\Helpers\ApiResponse;
 use App\Http\Controllers\Controller;
 use App\Http\Requests\Push\RegisterTokenRequest;
 use App\Http\Requests\Push\UpdateSettingsRequest;
 use App\Services\PushNotificationService;
-use App\Helpers\ApiResponse;
 use Illuminate\Http\Request;
 
 class PushNotificationController extends Controller
diff --git a/app/Http/Controllers/Api/V1/SaleController.php b/app/Http/Controllers/Api/V1/SaleController.php
index 9a1bcd1..942b6b3 100644
--- a/app/Http/Controllers/Api/V1/SaleController.php
+++ b/app/Http/Controllers/Api/V1/SaleController.php
@@ -4,6 +4,7 @@
 
 use App\Helpers\ApiResponse;
 use App\Http\Controllers\Controller;
+use App\Http\Requests\V1\Sale\SendStatementRequest;
 use App\Http\Requests\V1\Sale\StoreSaleRequest;
 use App\Http\Requests\V1\Sale\UpdateSaleRequest;
 use App\Services\SaleService;
@@ -103,4 +104,34 @@ public function summary(Request $request)
 
         return ApiResponse::success($summary, __('message.fetched'));
     }
+
+    /**
+     * 거래명세서 조회
+     */
+    public function getStatement(int $id)
+    {
+        $statement = $this->service->getStatement($id);
+
+        return ApiResponse::success($statement, __('message.fetched'));
+    }
+
+    /**
+     * 거래명세서 발행
+     */
+    public function issueStatement(int $id)
+    {
+        $result = $this->service->issueStatement($id);
+
+        return ApiResponse::success($result, __('message.sale.statement_issued'));
+    }
+
+    /**
+     * 거래명세서 이메일 발송
+     */
+    public function sendStatement(int $id, SendStatementRequest $request)
+    {
+        $result = $this->service->sendStatement($id, $request->validated());
+
+        return ApiResponse::success($result, __('message.sale.statement_sent'));
+    }
 }
diff --git a/app/Http/Controllers/Api/V1/UserInvitationController.php b/app/Http/Controllers/Api/V1/UserInvitationController.php
new file mode 100644
index 0000000..f714be4
--- /dev/null
+++ b/app/Http/Controllers/Api/V1/UserInvitationController.php
@@ -0,0 +1,73 @@
+<?php
+
+namespace App\Http\Controllers\Api\V1;
+
+use App\Helpers\ApiResponse;
+use App\Http\Controllers\Controller;
+use App\Http\Requests\UserInvitation\AcceptInvitationRequest;
+use App\Http\Requests\UserInvitation\InviteUserRequest;
+use App\Http\Requests\UserInvitation\ListInvitationRequest;
+use App\Services\UserInvitationService;
+use Illuminate\Http\JsonResponse;
+
+class UserInvitationController extends Controller
+{
+    public function __construct(
+        private readonly UserInvitationService $service
+    ) {}
+
+    /**
+     * 초대 목록 조회
+     */
+    public function index(ListInvitationRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->index($request->validated()),
+            __('message.fetched')
+        );
+    }
+
+    /**
+     * 사용자 초대 발송
+     */
+    public function invite(InviteUserRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->invite($request->validated()),
+            __('message.invitation.sent')
+        );
+    }
+
+    /**
+     * 초대 수락
+     */
+    public function accept(string $token, AcceptInvitationRequest $request): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->accept($token, $request->validated()),
+            __('message.invitation.accepted')
+        );
+    }
+
+    /**
+     * 초대 취소
+     */
+    public function cancel(int $id): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->cancel($id),
+            __('message.invitation.cancelled')
+        );
+    }
+
+    /**
+     * 초대 재발송
+     */
+    public function resend(int $id): JsonResponse
+    {
+        return ApiResponse::handle(
+            fn () => $this->service->resend($id),
+            __('message.invitation.resent')
+        );
+    }
+}
diff --git a/app/Http/Requests/Account/UpdateAgreementsRequest.php b/app/Http/Requests/Account/UpdateAgreementsRequest.php
new file mode 100644
index 0000000..1e12b5a
--- /dev/null
+++ b/app/Http/Requests/Account/UpdateAgreementsRequest.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace App\Http\Requests\Account;
+
+use App\Services\AccountService;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class UpdateAgreementsRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'agreements' => ['required', 'array', 'min:1'],
+            'agreements.*.type' => ['required', 'string', Rule::in(array_keys(AccountService::getAgreementTypes()))],
+            'agreements.*.agreed' => ['required', 'boolean'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'agreements.required' => __('validation.required', ['attribute' => '약관 동의 정보']),
+            'agreements.array' => __('validation.array', ['attribute' => '약관 동의 정보']),
+            'agreements.*.type.required' => __('validation.required', ['attribute' => '약관 유형']),
+            'agreements.*.type.in' => __('validation.in', ['attribute' => '약관 유형']),
+            'agreements.*.agreed.required' => __('validation.required', ['attribute' => '동의 여부']),
+            'agreements.*.agreed.boolean' => __('validation.boolean', ['attribute' => '동의 여부']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/Account/WithdrawRequest.php b/app/Http/Requests/Account/WithdrawRequest.php
new file mode 100644
index 0000000..f0026d6
--- /dev/null
+++ b/app/Http/Requests/Account/WithdrawRequest.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace App\Http\Requests\Account;
+
+use App\Services\AccountService;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class WithdrawRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'password' => ['required', 'string'],
+            'reason' => ['nullable', 'string', Rule::in(array_keys(AccountService::getWithdrawalReasons()))],
+            'detail' => ['nullable', 'string', 'max:500'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'password.required' => __('validation.required', ['attribute' => '비밀번호']),
+            'reason.in' => __('validation.in', ['attribute' => '탈퇴 사유']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/NotificationSetting/BulkUpdateSettingRequest.php b/app/Http/Requests/NotificationSetting/BulkUpdateSettingRequest.php
new file mode 100644
index 0000000..c8dd2fa
--- /dev/null
+++ b/app/Http/Requests/NotificationSetting/BulkUpdateSettingRequest.php
@@ -0,0 +1,39 @@
+<?php
+
+namespace App\Http\Requests\NotificationSetting;
+
+use App\Models\NotificationSetting;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class BulkUpdateSettingRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'settings' => ['required', 'array', 'min:1'],
+            'settings.*.notification_type' => ['required', 'string', Rule::in(NotificationSetting::getAllTypes())],
+            'settings.*.push_enabled' => ['nullable', 'boolean'],
+            'settings.*.email_enabled' => ['nullable', 'boolean'],
+            'settings.*.sms_enabled' => ['nullable', 'boolean'],
+            'settings.*.in_app_enabled' => ['nullable', 'boolean'],
+            'settings.*.kakao_enabled' => ['nullable', 'boolean'],
+            'settings.*.settings' => ['nullable', 'array'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'settings.required' => __('validation.required', ['attribute' => '설정']),
+            'settings.array' => __('validation.array', ['attribute' => '설정']),
+            'settings.*.notification_type.required' => __('validation.required', ['attribute' => '알림 유형']),
+            'settings.*.notification_type.in' => __('validation.in', ['attribute' => '알림 유형']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/NotificationSetting/UpdateSettingRequest.php b/app/Http/Requests/NotificationSetting/UpdateSettingRequest.php
new file mode 100644
index 0000000..585904f
--- /dev/null
+++ b/app/Http/Requests/NotificationSetting/UpdateSettingRequest.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace App\Http\Requests\NotificationSetting;
+
+use App\Models\NotificationSetting;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class UpdateSettingRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'notification_type' => ['required', 'string', Rule::in(NotificationSetting::getAllTypes())],
+            'push_enabled' => ['nullable', 'boolean'],
+            'email_enabled' => ['nullable', 'boolean'],
+            'sms_enabled' => ['nullable', 'boolean'],
+            'in_app_enabled' => ['nullable', 'boolean'],
+            'kakao_enabled' => ['nullable', 'boolean'],
+            'settings' => ['nullable', 'array'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'notification_type.required' => __('validation.required', ['attribute' => '알림 유형']),
+            'notification_type.in' => __('validation.in', ['attribute' => '알림 유형']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/UserInvitation/AcceptInvitationRequest.php b/app/Http/Requests/UserInvitation/AcceptInvitationRequest.php
new file mode 100644
index 0000000..bb8c4ff
--- /dev/null
+++ b/app/Http/Requests/UserInvitation/AcceptInvitationRequest.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace App\Http\Requests\UserInvitation;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class AcceptInvitationRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'name' => ['required', 'string', 'max:100'],
+            'password' => ['required', 'string', 'min:8', 'confirmed'],
+            'phone' => ['nullable', 'string', 'max:20'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'name.required' => __('validation.required', ['attribute' => '이름']),
+            'password.required' => __('validation.required', ['attribute' => '비밀번호']),
+            'password.min' => __('validation.min.string', ['attribute' => '비밀번호', 'min' => 8]),
+            'password.confirmed' => __('validation.confirmed', ['attribute' => '비밀번호']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/UserInvitation/InviteUserRequest.php b/app/Http/Requests/UserInvitation/InviteUserRequest.php
new file mode 100644
index 0000000..9757892
--- /dev/null
+++ b/app/Http/Requests/UserInvitation/InviteUserRequest.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace App\Http\Requests\UserInvitation;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class InviteUserRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'email' => ['required', 'email', 'max:255'],
+            'role_id' => ['nullable', 'integer', 'exists:roles,id'],
+            'message' => ['nullable', 'string', 'max:1000'],
+            'expires_days' => ['nullable', 'integer', 'min:1', 'max:30'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'email.required' => __('validation.required', ['attribute' => '이메일']),
+            'email.email' => __('validation.email', ['attribute' => '이메일']),
+            'role_id.exists' => __('validation.exists', ['attribute' => '역할']),
+        ];
+    }
+}
diff --git a/app/Http/Requests/UserInvitation/ListInvitationRequest.php b/app/Http/Requests/UserInvitation/ListInvitationRequest.php
new file mode 100644
index 0000000..fc23c50
--- /dev/null
+++ b/app/Http/Requests/UserInvitation/ListInvitationRequest.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace App\Http\Requests\UserInvitation;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class ListInvitationRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'status' => ['nullable', 'string', 'in:pending,accepted,expired,cancelled'],
+            'search' => ['nullable', 'string', 'max:255'],
+            'sort_by' => ['nullable', 'string', 'in:created_at,expires_at,email'],
+            'sort_dir' => ['nullable', 'string', 'in:asc,desc'],
+            'per_page' => ['nullable', 'integer', 'min:1', 'max:100'],
+            'page' => ['nullable', 'integer', 'min:1'],
+        ];
+    }
+}
diff --git a/app/Http/Requests/V1/Sale/SendStatementRequest.php b/app/Http/Requests/V1/Sale/SendStatementRequest.php
new file mode 100644
index 0000000..5c43074
--- /dev/null
+++ b/app/Http/Requests/V1/Sale/SendStatementRequest.php
@@ -0,0 +1,16 @@
+<?php
+
+namespace App\Http\Requests\V1\Sale;
+
+use App\Http\Requests\BaseRequest;
+
+class SendStatementRequest extends BaseRequest
+{
+    public function rules(): array
+    {
+        return [
+            'email' => ['nullable', 'string', 'email', 'max:255'],
+            'message' => ['nullable', 'string', 'max:1000'],
+        ];
+    }
+}
diff --git a/app/Models/NotificationSetting.php b/app/Models/NotificationSetting.php
new file mode 100644
index 0000000..bed7dc6
--- /dev/null
+++ b/app/Models/NotificationSetting.php
@@ -0,0 +1,226 @@
+<?php
+
+namespace App\Models;
+
+use App\Traits\BelongsToTenant;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class NotificationSetting extends Model
+{
+    use BelongsToTenant;
+
+    protected $fillable = [
+        'tenant_id',
+        'user_id',
+        'notification_type',
+        'push_enabled',
+        'email_enabled',
+        'sms_enabled',
+        'in_app_enabled',
+        'kakao_enabled',
+        'settings',
+    ];
+
+    protected $casts = [
+        'push_enabled' => 'boolean',
+        'email_enabled' => 'boolean',
+        'sms_enabled' => 'boolean',
+        'in_app_enabled' => 'boolean',
+        'kakao_enabled' => 'boolean',
+        'settings' => 'array',
+    ];
+
+    /**
+     * 알림 유형 상수
+     */
+    public const TYPE_APPROVAL = 'approval';           // 결재
+
+    public const TYPE_ORDER = 'order';                 // 수주
+
+    public const TYPE_DEPOSIT = 'deposit';             // 입금
+
+    public const TYPE_WITHDRAWAL = 'withdrawal';       // 출금
+
+    public const TYPE_NOTICE = 'notice';               // 공지사항
+
+    public const TYPE_SYSTEM = 'system';               // 시스템
+
+    public const TYPE_MARKETING = 'marketing';         // 마케팅
+
+    public const TYPE_SECURITY = 'security';           // 보안 (로그인, 비밀번호 변경 등)
+
+    /**
+     * 알림 채널 상수
+     */
+    public const CHANNEL_PUSH = 'push';
+
+    public const CHANNEL_EMAIL = 'email';
+
+    public const CHANNEL_SMS = 'sms';
+
+    public const CHANNEL_IN_APP = 'in_app';
+
+    public const CHANNEL_KAKAO = 'kakao';
+
+    /**
+     * 모든 알림 유형 반환
+     */
+    public static function getAllTypes(): array
+    {
+        return [
+            self::TYPE_APPROVAL,
+            self::TYPE_ORDER,
+            self::TYPE_DEPOSIT,
+            self::TYPE_WITHDRAWAL,
+            self::TYPE_NOTICE,
+            self::TYPE_SYSTEM,
+            self::TYPE_MARKETING,
+            self::TYPE_SECURITY,
+        ];
+    }
+
+    /**
+     * 모든 채널 반환
+     */
+    public static function getAllChannels(): array
+    {
+        return [
+            self::CHANNEL_PUSH,
+            self::CHANNEL_EMAIL,
+            self::CHANNEL_SMS,
+            self::CHANNEL_IN_APP,
+            self::CHANNEL_KAKAO,
+        ];
+    }
+
+    /**
+     * 알림 유형별 기본 설정 반환
+     */
+    public static function getDefaultSettings(string $type): array
+    {
+        // 보안 관련 알림은 이메일 기본 활성화
+        if ($type === self::TYPE_SECURITY) {
+            return [
+                'push_enabled' => true,
+                'email_enabled' => true,
+                'sms_enabled' => false,
+                'in_app_enabled' => true,
+                'kakao_enabled' => false,
+            ];
+        }
+
+        // 마케팅은 기본 비활성화
+        if ($type === self::TYPE_MARKETING) {
+            return [
+                'push_enabled' => false,
+                'email_enabled' => false,
+                'sms_enabled' => false,
+                'in_app_enabled' => false,
+                'kakao_enabled' => false,
+            ];
+        }
+
+        // 기타 알림은 푸시, 인앱만 기본 활성화
+        return [
+            'push_enabled' => true,
+            'email_enabled' => false,
+            'sms_enabled' => false,
+            'in_app_enabled' => true,
+            'kakao_enabled' => false,
+        ];
+    }
+
+    /**
+     * 알림 유형 레이블
+     */
+    public static function getTypeLabels(): array
+    {
+        return [
+            self::TYPE_APPROVAL => '전자결재',
+            self::TYPE_ORDER => '수주',
+            self::TYPE_DEPOSIT => '입금',
+            self::TYPE_WITHDRAWAL => '출금',
+            self::TYPE_NOTICE => '공지사항',
+            self::TYPE_SYSTEM => '시스템',
+            self::TYPE_MARKETING => '마케팅',
+            self::TYPE_SECURITY => '보안',
+        ];
+    }
+
+    /**
+     * 채널 레이블
+     */
+    public static function getChannelLabels(): array
+    {
+        return [
+            self::CHANNEL_PUSH => '푸시 알림',
+            self::CHANNEL_EMAIL => '이메일',
+            self::CHANNEL_SMS => 'SMS',
+            self::CHANNEL_IN_APP => '인앱 알림',
+            self::CHANNEL_KAKAO => '카카오 알림톡',
+        ];
+    }
+
+    /**
+     * 사용자 관계
+     */
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    /**
+     * 테넌트 관계
+     */
+    public function tenant(): BelongsTo
+    {
+        return $this->belongsTo(Tenant::class);
+    }
+
+    /**
+     * Scope: 특정 사용자의 설정
+     */
+    public function scopeForUser($query, int $userId)
+    {
+        return $query->where('user_id', $userId);
+    }
+
+    /**
+     * Scope: 특정 알림 유형
+     */
+    public function scopeOfType($query, string $type)
+    {
+        return $query->where('notification_type', $type);
+    }
+
+    /**
+     * 특정 채널이 활성화되어 있는지 확인
+     */
+    public function isChannelEnabled(string $channel): bool
+    {
+        return match ($channel) {
+            self::CHANNEL_PUSH => $this->push_enabled,
+            self::CHANNEL_EMAIL => $this->email_enabled,
+            self::CHANNEL_SMS => $this->sms_enabled,
+            self::CHANNEL_IN_APP => $this->in_app_enabled,
+            self::CHANNEL_KAKAO => $this->kakao_enabled,
+            default => false,
+        };
+    }
+
+    /**
+     * 채널 설정 업데이트
+     */
+    public function setChannelEnabled(string $channel, bool $enabled): void
+    {
+        match ($channel) {
+            self::CHANNEL_PUSH => $this->push_enabled = $enabled,
+            self::CHANNEL_EMAIL => $this->email_enabled = $enabled,
+            self::CHANNEL_SMS => $this->sms_enabled = $enabled,
+            self::CHANNEL_IN_APP => $this->in_app_enabled = $enabled,
+            self::CHANNEL_KAKAO => $this->kakao_enabled = $enabled,
+            default => null,
+        };
+    }
+}
diff --git a/app/Models/UserInvitation.php b/app/Models/UserInvitation.php
new file mode 100644
index 0000000..799f802
--- /dev/null
+++ b/app/Models/UserInvitation.php
@@ -0,0 +1,176 @@
+<?php
+
+namespace App\Models;
+
+use App\Models\Members\User;
+use App\Models\Permissions\Role;
+use App\Models\Tenants\Tenant;
+use App\Traits\BelongsToTenant;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Support\Str;
+
+class UserInvitation extends Model
+{
+    use BelongsToTenant;
+
+    // 상태 상수
+    public const STATUS_PENDING = 'pending';
+
+    public const STATUS_ACCEPTED = 'accepted';
+
+    public const STATUS_EXPIRED = 'expired';
+
+    public const STATUS_CANCELLED = 'cancelled';
+
+    // 기본 만료 기간 (일)
+    public const DEFAULT_EXPIRES_DAYS = 7;
+
+    protected $fillable = [
+        'tenant_id',
+        'email',
+        'role_id',
+        'message',
+        'token',
+        'status',
+        'invited_by',
+        'expires_at',
+        'accepted_at',
+    ];
+
+    protected $casts = [
+        'expires_at' => 'datetime',
+        'accepted_at' => 'datetime',
+    ];
+
+    /**
+     * 테넌트 관계
+     */
+    public function tenant(): BelongsTo
+    {
+        return $this->belongsTo(Tenant::class);
+    }
+
+    /**
+     * 역할 관계
+     */
+    public function role(): BelongsTo
+    {
+        return $this->belongsTo(Role::class);
+    }
+
+    /**
+     * 초대한 사용자 관계
+     */
+    public function inviter(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'invited_by');
+    }
+
+    /**
+     * 토큰 생성
+     */
+    public static function generateToken(): string
+    {
+        return Str::random(64);
+    }
+
+    /**
+     * 만료 일시 계산
+     */
+    public static function calculateExpiresAt(int $days = self::DEFAULT_EXPIRES_DAYS): \DateTime
+    {
+        return now()->addDays($days);
+    }
+
+    /**
+     * 만료 여부 확인
+     */
+    public function isExpired(): bool
+    {
+        return $this->expires_at->isPast();
+    }
+
+    /**
+     * 수락 가능 여부 확인
+     */
+    public function canAccept(): bool
+    {
+        return $this->status === self::STATUS_PENDING && ! $this->isExpired();
+    }
+
+    /**
+     * 취소 가능 여부 확인
+     */
+    public function canCancel(): bool
+    {
+        return $this->status === self::STATUS_PENDING;
+    }
+
+    /**
+     * 초대 수락 처리
+     */
+    public function markAsAccepted(): void
+    {
+        $this->status = self::STATUS_ACCEPTED;
+        $this->accepted_at = now();
+        $this->save();
+    }
+
+    /**
+     * 초대 만료 처리
+     */
+    public function markAsExpired(): void
+    {
+        $this->status = self::STATUS_EXPIRED;
+        $this->save();
+    }
+
+    /**
+     * 초대 취소 처리
+     */
+    public function markAsCancelled(): void
+    {
+        $this->status = self::STATUS_CANCELLED;
+        $this->save();
+    }
+
+    /**
+     * Scope: 대기 중인 초대만
+     */
+    public function scopePending($query)
+    {
+        return $query->where('status', self::STATUS_PENDING);
+    }
+
+    /**
+     * Scope: 만료된 초대 (상태 업데이트 대상)
+     */
+    public function scopeExpiredPending($query)
+    {
+        return $query->where('status', self::STATUS_PENDING)
+            ->where('expires_at', '<', now());
+    }
+
+    /**
+     * Scope: 특정 이메일 초대
+     */
+    public function scopeForEmail($query, string $email)
+    {
+        return $query->where('email', $email);
+    }
+
+    /**
+     * 상태 라벨 반환
+     */
+    public function getStatusLabelAttribute(): string
+    {
+        return match ($this->status) {
+            self::STATUS_PENDING => '대기중',
+            self::STATUS_ACCEPTED => '수락됨',
+            self::STATUS_EXPIRED => '만료됨',
+            self::STATUS_CANCELLED => '취소됨',
+            default => $this->status,
+        };
+    }
+}
diff --git a/app/Services/AccountService.php b/app/Services/AccountService.php
new file mode 100644
index 0000000..7d9bbfb
--- /dev/null
+++ b/app/Services/AccountService.php
@@ -0,0 +1,240 @@
+<?php
+
+namespace App\Services;
+
+use App\Models\Members\User;
+use App\Models\Members\UserTenant;
+use Illuminate\Support\Facades\DB;
+use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+class AccountService extends Service
+{
+    /**
+     * 회원 탈퇴 (SAM 완전 탈퇴)
+     * - 모든 테넌트에서 탈퇴
+     * - 사용자 계정 Soft Delete
+     */
+    public function withdraw(array $data): array
+    {
+        $userId = $this->apiUserId();
+        $user = User::find($userId);
+
+        if (! $user) {
+            throw new NotFoundHttpException(__('error.not_found_resource', ['resource' => '사용자']));
+        }
+
+        // 비밀번호 확인
+        if (! password_verify($data['password'], $user->password)) {
+            throw new BadRequestHttpException(__('error.account.invalid_password'));
+        }
+
+        return DB::transaction(function () use ($user, $data) {
+            // 1. 모든 테넌트 연결 해제 (soft delete)
+            UserTenant::where('user_id', $user->id)->delete();
+
+            // 2. 탈퇴 사유 저장 (options에 기록)
+            $options = $user->options ?? [];
+            $options['withdrawal'] = [
+                'reason' => $data['reason'] ?? null,
+                'detail' => $data['detail'] ?? null,
+                'withdrawn_at' => now()->toIso8601String(),
+            ];
+            $user->options = $options;
+            $user->save();
+
+            // 3. 사용자 soft delete
+            $user->delete();
+
+            // 4. 토큰 삭제
+            $user->tokens()->delete();
+
+            return [
+                'withdrawn_at' => now()->toIso8601String(),
+            ];
+        });
+    }
+
+    /**
+     * 사용 중지 (특정 테넌트에서만 탈퇴)
+     */
+    public function suspend(): array
+    {
+        $userId = $this->apiUserId();
+        $tenantId = $this->tenantId();
+
+        $userTenant = UserTenant::where('user_id', $userId)
+            ->where('tenant_id', $tenantId)
+            ->first();
+
+        if (! $userTenant) {
+            throw new NotFoundHttpException(__('error.account.tenant_membership_not_found'));
+        }
+
+        return DB::transaction(function () use ($userTenant, $userId, $tenantId) {
+            // 1. 현재 테넌트에서 비활성화
+            $userTenant->is_active = false;
+            $userTenant->left_at = now();
+            $userTenant->save();
+
+            // 2. 다른 활성 테넌트가 있으면 기본 테넌트 변경
+            $otherActiveTenant = UserTenant::where('user_id', $userId)
+                ->where('tenant_id', '!=', $tenantId)
+                ->where('is_active', true)
+                ->first();
+
+            if ($otherActiveTenant) {
+                // 다른 테넌트로 기본 변경
+                UserTenant::where('user_id', $userId)->update(['is_default' => false]);
+                $otherActiveTenant->is_default = true;
+                $otherActiveTenant->save();
+
+                return [
+                    'suspended' => true,
+                    'new_default_tenant_id' => $otherActiveTenant->tenant_id,
+                ];
+            }
+
+            return [
+                'suspended' => true,
+                'new_default_tenant_id' => null,
+            ];
+        });
+    }
+
+    /**
+     * 약관 동의 정보 조회
+     */
+    public function getAgreements(): array
+    {
+        $userId = $this->apiUserId();
+        $user = User::find($userId);
+
+        if (! $user) {
+            throw new NotFoundHttpException(__('error.not_found_resource', ['resource' => '사용자']));
+        }
+
+        $options = $user->options ?? [];
+        $agreements = $options['agreements'] ?? self::getDefaultAgreements();
+
+        return [
+            'agreements' => $agreements,
+            'types' => self::getAgreementTypes(),
+        ];
+    }
+
+    /**
+     * 약관 동의 정보 수정
+     */
+    public function updateAgreements(array $data): array
+    {
+        $userId = $this->apiUserId();
+        $user = User::find($userId);
+
+        if (! $user) {
+            throw new NotFoundHttpException(__('error.not_found_resource', ['resource' => '사용자']));
+        }
+
+        $options = $user->options ?? [];
+        $currentAgreements = $options['agreements'] ?? self::getDefaultAgreements();
+
+        // 수신 데이터로 업데이트
+        foreach ($data['agreements'] as $agreement) {
+            $type = $agreement['type'];
+            if (isset($currentAgreements[$type])) {
+                $currentAgreements[$type]['agreed'] = $agreement['agreed'];
+                $currentAgreements[$type]['agreed_at'] = $agreement['agreed']
+                    ? now()->toIso8601String()
+                    : null;
+            }
+        }
+
+        $options['agreements'] = $currentAgreements;
+        $user->options = $options;
+        $user->save();
+
+        return [
+            'agreements' => $currentAgreements,
+        ];
+    }
+
+    /**
+     * 기본 약관 동의 항목
+     */
+    public static function getDefaultAgreements(): array
+    {
+        return [
+            'terms' => [
+                'type' => 'terms',
+                'label' => '이용약관',
+                'required' => true,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+            'privacy' => [
+                'type' => 'privacy',
+                'label' => '개인정보 처리방침',
+                'required' => true,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+            'marketing' => [
+                'type' => 'marketing',
+                'label' => '마케팅 정보 수신',
+                'required' => false,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+            'push' => [
+                'type' => 'push',
+                'label' => '푸시 알림 수신',
+                'required' => false,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+            'email' => [
+                'type' => 'email',
+                'label' => '이메일 수신',
+                'required' => false,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+            'sms' => [
+                'type' => 'sms',
+                'label' => 'SMS 수신',
+                'required' => false,
+                'agreed' => false,
+                'agreed_at' => null,
+            ],
+        ];
+    }
+
+    /**
+     * 약관 유형 레이블
+     */
+    public static function getAgreementTypes(): array
+    {
+        return [
+            'terms' => '이용약관',
+            'privacy' => '개인정보 처리방침',
+            'marketing' => '마케팅 정보 수신',
+            'push' => '푸시 알림 수신',
+            'email' => '이메일 수신',
+            'sms' => 'SMS 수신',
+        ];
+    }
+
+    /**
+     * 탈퇴 사유 목록
+     */
+    public static function getWithdrawalReasons(): array
+    {
+        return [
+            'not_using' => '서비스를 더 이상 사용하지 않음',
+            'difficult' => '사용하기 어려움',
+            'alternative' => '다른 서비스 이용',
+            'privacy' => '개인정보 보호 우려',
+            'other' => '기타',
+        ];
+    }
+}
diff --git a/app/Services/NotificationSettingService.php b/app/Services/NotificationSettingService.php
new file mode 100644
index 0000000..01c6216
--- /dev/null
+++ b/app/Services/NotificationSettingService.php
@@ -0,0 +1,180 @@
+<?php
+
+namespace App\Services;
+
+use App\Models\NotificationSetting;
+use Illuminate\Support\Collection;
+use Illuminate\Support\Facades\DB;
+
+class NotificationSettingService extends Service
+{
+    /**
+     * 사용자의 알림 설정 조회
+     */
+    public function getSettings(): array
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        $settings = NotificationSetting::where('tenant_id', $tenantId)
+            ->forUser($userId)
+            ->get()
+            ->keyBy('notification_type');
+
+        // 모든 알림 유형에 대한 설정 반환 (없으면 기본값)
+        $result = [];
+        foreach (NotificationSetting::getAllTypes() as $type) {
+            if ($settings->has($type)) {
+                $setting = $settings->get($type);
+                $result[$type] = [
+                    'notification_type' => $type,
+                    'label' => NotificationSetting::getTypeLabels()[$type] ?? $type,
+                    'push_enabled' => $setting->push_enabled,
+                    'email_enabled' => $setting->email_enabled,
+                    'sms_enabled' => $setting->sms_enabled,
+                    'in_app_enabled' => $setting->in_app_enabled,
+                    'kakao_enabled' => $setting->kakao_enabled,
+                    'settings' => $setting->settings,
+                ];
+            } else {
+                $defaults = NotificationSetting::getDefaultSettings($type);
+                $result[$type] = array_merge([
+                    'notification_type' => $type,
+                    'label' => NotificationSetting::getTypeLabels()[$type] ?? $type,
+                    'settings' => null,
+                ], $defaults);
+            }
+        }
+
+        return [
+            'settings' => $result,
+            'types' => NotificationSetting::getTypeLabels(),
+            'channels' => NotificationSetting::getChannelLabels(),
+        ];
+    }
+
+    /**
+     * 특정 알림 유형 설정 업데이트
+     */
+    public function updateSetting(array $data): NotificationSetting
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        $notificationType = $data['notification_type'];
+
+        // 알림 유형 유효성 검증
+        if (! in_array($notificationType, NotificationSetting::getAllTypes(), true)) {
+            throw new \InvalidArgumentException(__('error.notification.invalid_type'));
+        }
+
+        return NotificationSetting::updateOrCreate(
+            [
+                'tenant_id' => $tenantId,
+                'user_id' => $userId,
+                'notification_type' => $notificationType,
+            ],
+            [
+                'push_enabled' => $data['push_enabled'] ?? true,
+                'email_enabled' => $data['email_enabled'] ?? false,
+                'sms_enabled' => $data['sms_enabled'] ?? false,
+                'in_app_enabled' => $data['in_app_enabled'] ?? true,
+                'kakao_enabled' => $data['kakao_enabled'] ?? false,
+                'settings' => $data['settings'] ?? null,
+            ]
+        );
+    }
+
+    /**
+     * 알림 설정 일괄 업데이트
+     */
+    public function bulkUpdateSettings(array $settings): Collection
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        return DB::transaction(function () use ($tenantId, $userId, $settings) {
+            $updated = collect();
+
+            foreach ($settings as $setting) {
+                $notificationType = $setting['notification_type'];
+
+                // 알림 유형 유효성 검증
+                if (! in_array($notificationType, NotificationSetting::getAllTypes(), true)) {
+                    continue;
+                }
+
+                $record = NotificationSetting::updateOrCreate(
+                    [
+                        'tenant_id' => $tenantId,
+                        'user_id' => $userId,
+                        'notification_type' => $notificationType,
+                    ],
+                    [
+                        'push_enabled' => $setting['push_enabled'] ?? true,
+                        'email_enabled' => $setting['email_enabled'] ?? false,
+                        'sms_enabled' => $setting['sms_enabled'] ?? false,
+                        'in_app_enabled' => $setting['in_app_enabled'] ?? true,
+                        'kakao_enabled' => $setting['kakao_enabled'] ?? false,
+                        'settings' => $setting['settings'] ?? null,
+                    ]
+                );
+
+                $updated->push($record);
+            }
+
+            return $updated;
+        });
+    }
+
+    /**
+     * 기본 알림 설정 초기화
+     */
+    public function initializeDefaultSettings(): void
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        foreach (NotificationSetting::getAllTypes() as $type) {
+            $defaults = NotificationSetting::getDefaultSettings($type);
+
+            NotificationSetting::firstOrCreate(
+                [
+                    'tenant_id' => $tenantId,
+                    'user_id' => $userId,
+                    'notification_type' => $type,
+                ],
+                $defaults
+            );
+        }
+    }
+
+    /**
+     * 특정 알림 유형에서 특정 채널이 활성화되어 있는지 확인
+     */
+    public function isChannelEnabled(int $userId, string $notificationType, string $channel): bool
+    {
+        $tenantId = $this->tenantId();
+
+        $setting = NotificationSetting::where('tenant_id', $tenantId)
+            ->forUser($userId)
+            ->ofType($notificationType)
+            ->first();
+
+        if (! $setting) {
+            // 기본 설정 반환
+            $defaults = NotificationSetting::getDefaultSettings($notificationType);
+
+            return match ($channel) {
+                NotificationSetting::CHANNEL_PUSH => $defaults['push_enabled'],
+                NotificationSetting::CHANNEL_EMAIL => $defaults['email_enabled'],
+                NotificationSetting::CHANNEL_SMS => $defaults['sms_enabled'],
+                NotificationSetting::CHANNEL_IN_APP => $defaults['in_app_enabled'],
+                NotificationSetting::CHANNEL_KAKAO => $defaults['kakao_enabled'],
+                default => false,
+            };
+        }
+
+        return $setting->isChannelEnabled($channel);
+    }
+}
diff --git a/app/Services/SaleService.php b/app/Services/SaleService.php
index 8ec8ea6..985a3da 100644
--- a/app/Services/SaleService.php
+++ b/app/Services/SaleService.php
@@ -275,4 +275,155 @@ private function generateSaleNumber(int $tenantId, string $saleDate): string
 
         return $prefix.str_pad($newSeq, 4, '0', STR_PAD_LEFT);
     }
+
+    /**
+     * 거래명세서 조회
+     */
+    public function getStatement(int $id): array
+    {
+        $tenantId = $this->tenantId();
+
+        $sale = Sale::query()
+            ->where('tenant_id', $tenantId)
+            ->with(['client', 'deposit', 'creator:id,name'])
+            ->findOrFail($id);
+
+        // 거래명세서 데이터 구성
+        return [
+            'statement_number' => $this->generateStatementNumber($sale),
+            'issued_at' => $sale->statement_issued_at,
+            'sale' => $sale,
+            'seller' => $this->getSellerInfo($tenantId),
+            'buyer' => $this->getBuyerInfo($sale->client),
+            'items' => $this->getSaleItems($sale),
+            'summary' => [
+                'supply_amount' => $sale->supply_amount,
+                'tax_amount' => $sale->tax_amount,
+                'total_amount' => $sale->total_amount,
+            ],
+        ];
+    }
+
+    /**
+     * 거래명세서 발행
+     */
+    public function issueStatement(int $id): array
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        return DB::transaction(function () use ($id, $tenantId, $userId) {
+            $sale = Sale::query()
+                ->where('tenant_id', $tenantId)
+                ->findOrFail($id);
+
+            // 확정된 매출만 거래명세서 발행 가능
+            if ($sale->status !== 'confirmed') {
+                throw new \Exception(__('error.sale.statement_requires_confirmed'));
+            }
+
+            // 발행 시간 기록
+            $sale->statement_issued_at = now();
+            $sale->statement_issued_by = $userId;
+            $sale->save();
+
+            return [
+                'statement_number' => $this->generateStatementNumber($sale),
+                'issued_at' => $sale->statement_issued_at->toIso8601String(),
+            ];
+        });
+    }
+
+    /**
+     * 거래명세서 이메일 발송
+     */
+    public function sendStatement(int $id, array $data): array
+    {
+        $tenantId = $this->tenantId();
+
+        $sale = Sale::query()
+            ->where('tenant_id', $tenantId)
+            ->with(['client'])
+            ->findOrFail($id);
+
+        // 수신자 이메일 확인
+        $recipientEmail = $data['email'] ?? $sale->client?->email;
+        if (empty($recipientEmail)) {
+            throw new \Exception(__('error.sale.recipient_email_required'));
+        }
+
+        // TODO: 실제 이메일 발송 로직 구현
+        // Mail::to($recipientEmail)->send(new SaleStatementMail($sale, $data['message'] ?? null));
+
+        return [
+            'sent_to' => $recipientEmail,
+            'sent_at' => now()->toIso8601String(),
+            'statement_number' => $this->generateStatementNumber($sale),
+        ];
+    }
+
+    /**
+     * 거래명세서 번호 생성
+     */
+    private function generateStatementNumber(Sale $sale): string
+    {
+        return 'ST'.$sale->sale_number;
+    }
+
+    /**
+     * 판매자 정보 조회
+     */
+    private function getSellerInfo(int $tenantId): array
+    {
+        $tenant = \App\Models\Tenants\Tenant::find($tenantId);
+
+        return [
+            'name' => $tenant->name ?? '',
+            'business_number' => $tenant->business_number ?? '',
+            'representative' => $tenant->representative ?? '',
+            'address' => $tenant->address ?? '',
+            'tel' => $tenant->tel ?? '',
+            'fax' => $tenant->fax ?? '',
+            'email' => $tenant->email ?? '',
+        ];
+    }
+
+    /**
+     * 구매자 정보 조회
+     */
+    private function getBuyerInfo($client): array
+    {
+        if (! $client) {
+            return [];
+        }
+
+        return [
+            'name' => $client->name ?? '',
+            'business_number' => $client->business_number ?? '',
+            'representative' => $client->representative ?? '',
+            'address' => $client->address ?? '',
+            'tel' => $client->tel ?? '',
+            'fax' => $client->fax ?? '',
+            'email' => $client->email ?? '',
+        ];
+    }
+
+    /**
+     * 매출 품목 조회 (향후 확장)
+     */
+    private function getSaleItems(Sale $sale): array
+    {
+        // TODO: 매출 품목 테이블이 있다면 조회
+        // 현재는 기본 매출 정보만 반환
+        return [
+            [
+                'description' => $sale->description ?? '매출',
+                'quantity' => 1,
+                'unit_price' => $sale->supply_amount,
+                'supply_amount' => $sale->supply_amount,
+                'tax_amount' => $sale->tax_amount,
+                'total_amount' => $sale->total_amount,
+            ],
+        ];
+    }
 }
diff --git a/app/Services/UserInvitationService.php b/app/Services/UserInvitationService.php
new file mode 100644
index 0000000..8d55e2f
--- /dev/null
+++ b/app/Services/UserInvitationService.php
@@ -0,0 +1,230 @@
+<?php
+
+namespace App\Services;
+
+use App\Models\Members\User;
+use App\Models\Members\UserTenant;
+use App\Models\UserInvitation;
+use Illuminate\Contracts\Pagination\LengthAwarePaginator;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Mail;
+use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+class UserInvitationService extends Service
+{
+    /**
+     * 초대 목록 조회
+     */
+    public function index(array $params): LengthAwarePaginator
+    {
+        $tenantId = $this->tenantId();
+
+        $query = UserInvitation::query()
+            ->where('tenant_id', $tenantId)
+            ->with(['role:id,name', 'inviter:id,name']);
+
+        // 상태 필터
+        if (! empty($params['status'])) {
+            $query->where('status', $params['status']);
+        }
+
+        // 이메일 검색
+        if (! empty($params['search'])) {
+            $search = $params['search'];
+            $query->where(function ($q) use ($search) {
+                $q->where('email', 'like', "%{$search}%");
+            });
+        }
+
+        // 정렬
+        $sortBy = $params['sort_by'] ?? 'created_at';
+        $sortDir = $params['sort_dir'] ?? 'desc';
+        $query->orderBy($sortBy, $sortDir);
+
+        // 페이지네이션
+        $perPage = $params['per_page'] ?? 20;
+
+        return $query->paginate($perPage);
+    }
+
+    /**
+     * 사용자 초대 발송
+     */
+    public function invite(array $data): UserInvitation
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        return DB::transaction(function () use ($data, $tenantId, $userId) {
+            $email = $data['email'];
+
+            // 이미 테넌트에 가입된 사용자인지 확인
+            $existingUser = User::where('email', $email)->first();
+            if ($existingUser) {
+                $existingMembership = UserTenant::where('tenant_id', $tenantId)
+                    ->where('user_id', $existingUser->id)
+                    ->whereNull('deleted_at')
+                    ->exists();
+
+                if ($existingMembership) {
+                    throw new BadRequestHttpException(__('error.invitation.already_member'));
+                }
+            }
+
+            // 이미 대기 중인 초대가 있는지 확인
+            $pendingInvitation = UserInvitation::where('tenant_id', $tenantId)
+                ->where('email', $email)
+                ->pending()
+                ->first();
+
+            if ($pendingInvitation) {
+                throw new BadRequestHttpException(__('error.invitation.already_pending'));
+            }
+
+            // 초대 생성
+            $invitation = new UserInvitation;
+            $invitation->tenant_id = $tenantId;
+            $invitation->email = $email;
+            $invitation->role_id = $data['role_id'] ?? null;
+            $invitation->message = $data['message'] ?? null;
+            $invitation->token = UserInvitation::generateToken();
+            $invitation->status = UserInvitation::STATUS_PENDING;
+            $invitation->invited_by = $userId;
+            $invitation->expires_at = UserInvitation::calculateExpiresAt($data['expires_days'] ?? UserInvitation::DEFAULT_EXPIRES_DAYS);
+            $invitation->save();
+
+            // 초대 이메일 발송 (비동기 처리 권장)
+            $this->sendInvitationEmail($invitation);
+
+            return $invitation->load(['role:id,name', 'inviter:id,name']);
+        });
+    }
+
+    /**
+     * 초대 수락
+     */
+    public function accept(string $token, array $userData): User
+    {
+        return DB::transaction(function () use ($token, $userData) {
+            // 토큰으로 초대 조회 (테넌트 스코프 제외)
+            $invitation = UserInvitation::withoutGlobalScopes()
+                ->where('token', $token)
+                ->first();
+
+            if (! $invitation) {
+                throw new NotFoundHttpException(__('error.invitation.not_found'));
+            }
+
+            if (! $invitation->canAccept()) {
+                if ($invitation->isExpired()) {
+                    $invitation->markAsExpired();
+                    throw new BadRequestHttpException(__('error.invitation.expired'));
+                }
+                throw new BadRequestHttpException(__('error.invitation.invalid_status'));
+            }
+
+            // 기존 사용자 확인 또는 신규 생성
+            $user = User::where('email', $invitation->email)->first();
+
+            if (! $user) {
+                // 신규 사용자 생성
+                $user = new User;
+                $user->email = $invitation->email;
+                $user->name = $userData['name'];
+                $user->password = $userData['password'];
+                $user->phone = $userData['phone'] ?? null;
+                $user->save();
+            }
+
+            // 테넌트 멤버십 생성
+            $userTenant = new UserTenant;
+            $userTenant->user_id = $user->id;
+            $userTenant->tenant_id = $invitation->tenant_id;
+            $userTenant->is_active = true;
+            $userTenant->is_default = ! $user->userTenants()->exists(); // 첫 테넌트면 기본으로
+            $userTenant->joined_at = now();
+            $userTenant->save();
+
+            // 역할 부여 (있는 경우)
+            if ($invitation->role_id) {
+                $user->assignRole($invitation->role->name);
+            }
+
+            // 초대 수락 처리
+            $invitation->markAsAccepted();
+
+            return $user;
+        });
+    }
+
+    /**
+     * 초대 취소
+     */
+    public function cancel(int $id): bool
+    {
+        $tenantId = $this->tenantId();
+
+        $invitation = UserInvitation::where('tenant_id', $tenantId)
+            ->findOrFail($id);
+
+        if (! $invitation->canCancel()) {
+            throw new BadRequestHttpException(__('error.invitation.cannot_cancel'));
+        }
+
+        $invitation->markAsCancelled();
+
+        return true;
+    }
+
+    /**
+     * 초대 재발송
+     */
+    public function resend(int $id): UserInvitation
+    {
+        $tenantId = $this->tenantId();
+
+        $invitation = UserInvitation::where('tenant_id', $tenantId)
+            ->findOrFail($id);
+
+        if ($invitation->status !== UserInvitation::STATUS_PENDING) {
+            throw new BadRequestHttpException(__('error.invitation.cannot_resend'));
+        }
+
+        // 만료 기간 연장 및 토큰 재생성
+        $invitation->token = UserInvitation::generateToken();
+        $invitation->expires_at = UserInvitation::calculateExpiresAt();
+        $invitation->save();
+
+        // 이메일 재발송
+        $this->sendInvitationEmail($invitation);
+
+        return $invitation->load(['role:id,name', 'inviter:id,name']);
+    }
+
+    /**
+     * 만료된 초대 일괄 처리 (스케줄러용)
+     */
+    public function expirePendingInvitations(): int
+    {
+        return UserInvitation::withoutGlobalScopes()
+            ->expiredPending()
+            ->update(['status' => UserInvitation::STATUS_EXPIRED]);
+    }
+
+    /**
+     * 초대 이메일 발송
+     */
+    protected function sendInvitationEmail(UserInvitation $invitation): void
+    {
+        // TODO: 실제 메일 발송 로직 구현
+        // Mail::to($invitation->email)->queue(new UserInvitationMail($invitation));
+
+        // 현재는 로그로 대체
+        \Log::info('User invitation email sent', [
+            'email' => $invitation->email,
+            'token' => $invitation->token,
+            'tenant_id' => $invitation->tenant_id,
+        ]);
+    }
+}
diff --git a/app/Swagger/v1/AccountApi.php b/app/Swagger/v1/AccountApi.php
new file mode 100644
index 0000000..2624436
--- /dev/null
+++ b/app/Swagger/v1/AccountApi.php
@@ -0,0 +1,214 @@
+<?php
+
+namespace App\Swagger\v1;
+
+/**
+ * @OA\Tag(
+ *     name="Account",
+ *     description="계정 관리 (탈퇴, 사용중지, 약관동의)"
+ * )
+ *
+ * @OA\Schema(
+ *     schema="AgreementItem",
+ *     type="object",
+ *
+ *     @OA\Property(property="type", type="string", example="marketing"),
+ *     @OA\Property(property="label", type="string", example="마케팅 정보 수신"),
+ *     @OA\Property(property="required", type="boolean", example=false),
+ *     @OA\Property(property="agreed", type="boolean", example=true),
+ *     @OA\Property(property="agreed_at", type="string", format="date-time", nullable=true, example="2025-12-19T10:00:00+09:00")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="AgreementsResponse",
+ *     type="object",
+ *
+ *     @OA\Property(
+ *         property="agreements",
+ *         type="object",
+ *         additionalProperties={"$ref": "#/components/schemas/AgreementItem"}
+ *     ),
+ *     @OA\Property(
+ *         property="types",
+ *         type="object",
+ *         description="약관 유형 레이블",
+ *         example={"terms": "이용약관", "privacy": "개인정보 처리방침", "marketing": "마케팅 정보 수신"}
+ *     )
+ * )
+ *
+ * @OA\Schema(
+ *     schema="WithdrawRequest",
+ *     type="object",
+ *     required={"password"},
+ *
+ *     @OA\Property(property="password", type="string", example="currentPassword123", description="현재 비밀번호 (확인용)"),
+ *     @OA\Property(property="reason", type="string", enum={"not_using", "difficult", "alternative", "privacy", "other"}, example="not_using", description="탈퇴 사유"),
+ *     @OA\Property(property="detail", type="string", nullable=true, maxLength=500, example="더 이상 필요하지 않습니다.", description="상세 사유")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="WithdrawResponse",
+ *     type="object",
+ *
+ *     @OA\Property(property="withdrawn_at", type="string", format="date-time", example="2025-12-19T10:00:00+09:00")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SuspendResponse",
+ *     type="object",
+ *
+ *     @OA\Property(property="suspended", type="boolean", example=true),
+ *     @OA\Property(property="new_default_tenant_id", type="integer", nullable=true, example=2, description="새 기본 테넌트 ID (없으면 null)")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="UpdateAgreementsRequest",
+ *     type="object",
+ *     required={"agreements"},
+ *
+ *     @OA\Property(
+ *         property="agreements",
+ *         type="array",
+ *
+ *         @OA\Items(
+ *             type="object",
+ *             required={"type", "agreed"},
+ *
+ *             @OA\Property(property="type", type="string", enum={"terms", "privacy", "marketing", "push", "email", "sms"}, example="marketing"),
+ *             @OA\Property(property="agreed", type="boolean", example=true)
+ *         )
+ *     )
+ * )
+ */
+class AccountApi
+{
+    /**
+     * @OA\Post(
+     *     path="/api/v1/account/withdraw",
+     *     operationId="withdrawAccount",
+     *     tags={"Account"},
+     *     summary="회원 탈퇴",
+     *     description="SAM 회원 탈퇴 (모든 테넌트에서 탈퇴, 계정 삭제)",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/WithdrawRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="탈퇴 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="회원 탈퇴가 완료되었습니다."),
+     *             @OA\Property(property="data", ref="#/components/schemas/WithdrawResponse")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="비밀번호 불일치"),
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="사용자를 찾을 수 없음")
+     * )
+     */
+    public function withdraw() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/account/suspend",
+     *     operationId="suspendAccount",
+     *     tags={"Account"},
+     *     summary="사용 중지",
+     *     description="현재 테넌트에서만 탈퇴 (다른 테넌트 멤버십 유지)",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="사용 중지 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="사용 중지가 완료되었습니다."),
+     *             @OA\Property(property="data", ref="#/components/schemas/SuspendResponse")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="테넌트 멤버십을 찾을 수 없음")
+     * )
+     */
+    public function suspend() {}
+
+    /**
+     * @OA\Get(
+     *     path="/api/v1/account/agreements",
+     *     operationId="getAgreements",
+     *     tags={"Account"},
+     *     summary="약관 동의 정보 조회",
+     *     description="현재 사용자의 약관 동의 정보를 조회합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="조회 성공"),
+     *             @OA\Property(property="data", ref="#/components/schemas/AgreementsResponse")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="사용자를 찾을 수 없음")
+     * )
+     */
+    public function getAgreements() {}
+
+    /**
+     * @OA\Put(
+     *     path="/api/v1/account/agreements",
+     *     operationId="updateAgreements",
+     *     tags={"Account"},
+     *     summary="약관 동의 정보 수정",
+     *     description="약관 동의 정보를 수정합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/UpdateAgreementsRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="수정 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="수정 성공"),
+     *             @OA\Property(
+     *                 property="data",
+     *                 type="object",
+     *                 @OA\Property(
+     *                     property="agreements",
+     *                     type="object",
+     *                     additionalProperties={"$ref": "#/components/schemas/AgreementItem"}
+     *                 )
+     *             )
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="사용자를 찾을 수 없음"),
+     *     @OA\Response(response=422, description="유효성 검증 실패")
+     * )
+     */
+    public function updateAgreements() {}
+}
diff --git a/app/Swagger/v1/InternalApi.php b/app/Swagger/v1/InternalApi.php
index 3d90bf8..46c4987 100644
--- a/app/Swagger/v1/InternalApi.php
+++ b/app/Swagger/v1/InternalApi.php
@@ -70,8 +70,9 @@ class InternalApi
      *
      *         @OA\JsonContent(ref="#/components/schemas/ErrorResponse")
      *     ),
+     *
      *     @OA\Response(response=422, description="검증 실패", @OA\JsonContent(ref="#/components/schemas/ErrorResponse"))
      * )
      */
     public function exchangeToken() {}
-}
\ No newline at end of file
+}
diff --git a/app/Swagger/v1/NotificationSettingApi.php b/app/Swagger/v1/NotificationSettingApi.php
new file mode 100644
index 0000000..5df435a
--- /dev/null
+++ b/app/Swagger/v1/NotificationSettingApi.php
@@ -0,0 +1,173 @@
+<?php
+
+namespace App\Swagger\v1;
+
+/**
+ * @OA\Tag(
+ *     name="NotificationSetting",
+ *     description="알림 설정 관리"
+ * )
+ *
+ * @OA\Schema(
+ *     schema="NotificationSettingItem",
+ *     type="object",
+ *
+ *     @OA\Property(property="notification_type", type="string", example="approval"),
+ *     @OA\Property(property="label", type="string", example="전자결재"),
+ *     @OA\Property(property="push_enabled", type="boolean", example=true),
+ *     @OA\Property(property="email_enabled", type="boolean", example=false),
+ *     @OA\Property(property="sms_enabled", type="boolean", example=false),
+ *     @OA\Property(property="in_app_enabled", type="boolean", example=true),
+ *     @OA\Property(property="kakao_enabled", type="boolean", example=false),
+ *     @OA\Property(property="settings", type="object", nullable=true)
+ * )
+ *
+ * @OA\Schema(
+ *     schema="NotificationSettingResponse",
+ *     type="object",
+ *
+ *     @OA\Property(
+ *         property="settings",
+ *         type="object",
+ *         additionalProperties={"$ref": "#/components/schemas/NotificationSettingItem"}
+ *     ),
+ *     @OA\Property(
+ *         property="types",
+ *         type="object",
+ *         description="알림 유형 레이블",
+ *         example={"approval": "전자결재", "order": "수주", "deposit": "입금"}
+ *     ),
+ *     @OA\Property(
+ *         property="channels",
+ *         type="object",
+ *         description="채널 레이블",
+ *         example={"push": "푸시 알림", "email": "이메일", "sms": "SMS"}
+ *     )
+ * )
+ *
+ * @OA\Schema(
+ *     schema="UpdateNotificationSettingRequest",
+ *     type="object",
+ *     required={"notification_type"},
+ *
+ *     @OA\Property(property="notification_type", type="string", enum={"approval", "order", "deposit", "withdrawal", "notice", "system", "marketing", "security"}, example="approval", description="알림 유형"),
+ *     @OA\Property(property="push_enabled", type="boolean", nullable=true, example=true, description="푸시 알림 활성화"),
+ *     @OA\Property(property="email_enabled", type="boolean", nullable=true, example=false, description="이메일 알림 활성화"),
+ *     @OA\Property(property="sms_enabled", type="boolean", nullable=true, example=false, description="SMS 알림 활성화"),
+ *     @OA\Property(property="in_app_enabled", type="boolean", nullable=true, example=true, description="인앱 알림 활성화"),
+ *     @OA\Property(property="kakao_enabled", type="boolean", nullable=true, example=false, description="카카오 알림톡 활성화"),
+ *     @OA\Property(property="settings", type="object", nullable=true, description="추가 설정")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="BulkUpdateNotificationSettingRequest",
+ *     type="object",
+ *     required={"settings"},
+ *
+ *     @OA\Property(
+ *         property="settings",
+ *         type="array",
+ *
+ *         @OA\Items(ref="#/components/schemas/UpdateNotificationSettingRequest")
+ *     )
+ * )
+ */
+class NotificationSettingApi
+{
+    /**
+     * @OA\Get(
+     *     path="/api/v1/users/me/notification-settings",
+     *     operationId="getNotificationSettings",
+     *     tags={"NotificationSetting"},
+     *     summary="알림 설정 조회",
+     *     description="현재 사용자의 알림 설정을 조회합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="조회 성공"),
+     *             @OA\Property(property="data", ref="#/components/schemas/NotificationSettingResponse")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패")
+     * )
+     */
+    public function index() {}
+
+    /**
+     * @OA\Put(
+     *     path="/api/v1/users/me/notification-settings",
+     *     operationId="updateNotificationSetting",
+     *     tags={"NotificationSetting"},
+     *     summary="알림 설정 업데이트",
+     *     description="특정 알림 유형의 설정을 업데이트합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/UpdateNotificationSettingRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="수정 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="수정 성공"),
+     *             @OA\Property(property="data", ref="#/components/schemas/NotificationSettingItem")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=422, description="유효성 검증 실패")
+     * )
+     */
+    public function update() {}
+
+    /**
+     * @OA\Put(
+     *     path="/api/v1/users/me/notification-settings/bulk",
+     *     operationId="bulkUpdateNotificationSettings",
+     *     tags={"NotificationSetting"},
+     *     summary="알림 설정 일괄 업데이트",
+     *     description="여러 알림 유형의 설정을 일괄 업데이트합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/BulkUpdateNotificationSettingRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="일괄 저장 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="대량 저장 성공"),
+     *             @OA\Property(
+     *                 property="data",
+     *                 type="array",
+     *
+     *                 @OA\Items(ref="#/components/schemas/NotificationSettingItem")
+     *             )
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=422, description="유효성 검증 실패")
+     * )
+     */
+    public function bulkUpdate() {}
+}
diff --git a/app/Swagger/v1/SaleApi.php b/app/Swagger/v1/SaleApi.php
index 75b23c3..103e4b3 100644
--- a/app/Swagger/v1/SaleApi.php
+++ b/app/Swagger/v1/SaleApi.php
@@ -81,6 +81,79 @@
  *         )
  *     )
  * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatementItem",
+ *     type="object",
+ *     description="거래명세서 품목",
+ *
+ *     @OA\Property(property="description", type="string", example="1월 매출", description="품목 설명"),
+ *     @OA\Property(property="quantity", type="integer", example=1, description="수량"),
+ *     @OA\Property(property="unit_price", type="number", example=1000000, description="단가"),
+ *     @OA\Property(property="supply_amount", type="number", example=1000000, description="공급가액"),
+ *     @OA\Property(property="tax_amount", type="number", example=100000, description="세액"),
+ *     @OA\Property(property="total_amount", type="number", example=1100000, description="합계")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatementParty",
+ *     type="object",
+ *     description="거래명세서 거래 당사자 정보",
+ *
+ *     @OA\Property(property="name", type="string", example="(주)테스트", description="상호"),
+ *     @OA\Property(property="business_number", type="string", example="123-45-67890", description="사업자번호"),
+ *     @OA\Property(property="representative", type="string", example="홍길동", description="대표자"),
+ *     @OA\Property(property="address", type="string", example="서울시 강남구", description="주소"),
+ *     @OA\Property(property="tel", type="string", example="02-1234-5678", description="전화번호"),
+ *     @OA\Property(property="fax", type="string", example="02-1234-5679", description="팩스"),
+ *     @OA\Property(property="email", type="string", example="test@example.com", description="이메일")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatement",
+ *     type="object",
+ *     description="거래명세서 정보",
+ *
+ *     @OA\Property(property="statement_number", type="string", example="STSL202501150001", description="거래명세서 번호"),
+ *     @OA\Property(property="issued_at", type="string", format="date-time", nullable=true, description="발행일시"),
+ *     @OA\Property(property="sale", ref="#/components/schemas/Sale"),
+ *     @OA\Property(property="seller", ref="#/components/schemas/SaleStatementParty"),
+ *     @OA\Property(property="buyer", ref="#/components/schemas/SaleStatementParty"),
+ *     @OA\Property(property="items", type="array", @OA\Items(ref="#/components/schemas/SaleStatementItem")),
+ *     @OA\Property(property="summary", type="object",
+ *         @OA\Property(property="supply_amount", type="number", example=1000000),
+ *         @OA\Property(property="tax_amount", type="number", example=100000),
+ *         @OA\Property(property="total_amount", type="number", example=1100000)
+ *     )
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatementIssueResponse",
+ *     type="object",
+ *     description="거래명세서 발행 응답",
+ *
+ *     @OA\Property(property="statement_number", type="string", example="STSL202501150001", description="거래명세서 번호"),
+ *     @OA\Property(property="issued_at", type="string", format="date-time", example="2025-01-15T10:30:00+09:00", description="발행일시")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatementSendRequest",
+ *     type="object",
+ *     description="거래명세서 이메일 발송 요청",
+ *
+ *     @OA\Property(property="email", type="string", format="email", example="buyer@example.com", nullable=true, description="수신자 이메일 (미입력 시 거래처 이메일 사용)"),
+ *     @OA\Property(property="message", type="string", example="거래명세서를 발송합니다.", maxLength=1000, nullable=true, description="추가 메시지")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="SaleStatementSendResponse",
+ *     type="object",
+ *     description="거래명세서 발송 응답",
+ *
+ *     @OA\Property(property="sent_to", type="string", format="email", example="buyer@example.com", description="발송 이메일"),
+ *     @OA\Property(property="sent_at", type="string", format="date-time", example="2025-01-15T10:30:00+09:00", description="발송일시"),
+ *     @OA\Property(property="statement_number", type="string", example="STSL202501150001", description="거래명세서 번호")
+ * )
  */
 class SaleApi
 {
@@ -334,4 +407,111 @@ public function destroy() {}
      * )
      */
     public function confirm() {}
+
+    /**
+     * @OA\Get(
+     *     path="/api/v1/sales/{id}/statement",
+     *     tags={"Sales"},
+     *     summary="거래명세서 조회",
+     *     description="매출에 대한 거래명세서 정보를 조회합니다.",
+     *     security={{"ApiKeyAuth":{}},{"BearerAuth":{}}},
+     *
+     *     @OA\Parameter(name="id", in="path", required=true, description="매출 ID", @OA\Schema(type="integer")),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="조회 성공",
+     *
+     *         @OA\JsonContent(
+     *             allOf={
+     *
+     *                 @OA\Schema(ref="#/components/schemas/ApiResponse"),
+     *                 @OA\Schema(
+     *
+     *                     @OA\Property(property="data", ref="#/components/schemas/SaleStatement")
+     *                 )
+     *             }
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=404, description="매출 없음", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=500, description="서버 에러", @OA\JsonContent(ref="#/components/schemas/ErrorResponse"))
+     * )
+     */
+    public function getStatement() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/sales/{id}/statement/issue",
+     *     tags={"Sales"},
+     *     summary="거래명세서 발행",
+     *     description="매출에 대한 거래명세서를 발행합니다. 확정(confirmed) 상태의 매출만 발행 가능합니다.",
+     *     security={{"ApiKeyAuth":{}},{"BearerAuth":{}}},
+     *
+     *     @OA\Parameter(name="id", in="path", required=true, description="매출 ID", @OA\Schema(type="integer")),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="발행 성공",
+     *
+     *         @OA\JsonContent(
+     *             allOf={
+     *
+     *                 @OA\Schema(ref="#/components/schemas/ApiResponse"),
+     *                 @OA\Schema(
+     *
+     *                     @OA\Property(property="data", ref="#/components/schemas/SaleStatementIssueResponse")
+     *                 )
+     *             }
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="발행 불가 (미확정 상태)", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=401, description="인증 실패", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=404, description="매출 없음", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=500, description="서버 에러", @OA\JsonContent(ref="#/components/schemas/ErrorResponse"))
+     * )
+     */
+    public function issueStatement() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/sales/{id}/statement/send",
+     *     tags={"Sales"},
+     *     summary="거래명세서 이메일 발송",
+     *     description="거래명세서를 이메일로 발송합니다. 이메일 미입력 시 거래처 이메일로 발송됩니다.",
+     *     security={{"ApiKeyAuth":{}},{"BearerAuth":{}}},
+     *
+     *     @OA\Parameter(name="id", in="path", required=true, description="매출 ID", @OA\Schema(type="integer")),
+     *
+     *     @OA\RequestBody(
+     *         required=false,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/SaleStatementSendRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="발송 성공",
+     *
+     *         @OA\JsonContent(
+     *             allOf={
+     *
+     *                 @OA\Schema(ref="#/components/schemas/ApiResponse"),
+     *                 @OA\Schema(
+     *
+     *                     @OA\Property(property="data", ref="#/components/schemas/SaleStatementSendResponse")
+     *                 )
+     *             }
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="발송 불가 (이메일 없음)", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=401, description="인증 실패", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=404, description="매출 없음", @OA\JsonContent(ref="#/components/schemas/ErrorResponse")),
+     *     @OA\Response(response=500, description="서버 에러", @OA\JsonContent(ref="#/components/schemas/ErrorResponse"))
+     * )
+     */
+    public function sendStatement() {}
 }
diff --git a/app/Swagger/v1/UserInvitationApi.php b/app/Swagger/v1/UserInvitationApi.php
new file mode 100644
index 0000000..9360fc3
--- /dev/null
+++ b/app/Swagger/v1/UserInvitationApi.php
@@ -0,0 +1,311 @@
+<?php
+
+namespace App\Swagger\v1;
+
+/**
+ * @OA\Tag(
+ *     name="UserInvitation",
+ *     description="사용자 초대 관리"
+ * )
+ *
+ * @OA\Schema(
+ *     schema="UserInvitation",
+ *     type="object",
+ *     required={"id", "tenant_id", "email", "token", "status", "invited_by", "expires_at"},
+ *
+ *     @OA\Property(property="id", type="integer", example=1),
+ *     @OA\Property(property="tenant_id", type="integer", example=1),
+ *     @OA\Property(property="email", type="string", format="email", example="user@example.com"),
+ *     @OA\Property(property="role_id", type="integer", nullable=true, example=2),
+ *     @OA\Property(property="message", type="string", nullable=true, example="회사에 합류해 주세요!"),
+ *     @OA\Property(property="token", type="string", example="abc123..."),
+ *     @OA\Property(property="status", type="string", enum={"pending", "accepted", "expired", "cancelled"}, example="pending"),
+ *     @OA\Property(property="status_label", type="string", example="대기중"),
+ *     @OA\Property(property="invited_by", type="integer", example=1),
+ *     @OA\Property(property="expires_at", type="string", format="date-time"),
+ *     @OA\Property(property="accepted_at", type="string", format="date-time", nullable=true),
+ *     @OA\Property(property="created_at", type="string", format="date-time"),
+ *     @OA\Property(property="updated_at", type="string", format="date-time"),
+ *     @OA\Property(
+ *         property="role",
+ *         type="object",
+ *         nullable=true,
+ *         @OA\Property(property="id", type="integer"),
+ *         @OA\Property(property="name", type="string")
+ *     ),
+ *     @OA\Property(
+ *         property="inviter",
+ *         type="object",
+ *         @OA\Property(property="id", type="integer"),
+ *         @OA\Property(property="name", type="string")
+ *     )
+ * )
+ *
+ * @OA\Schema(
+ *     schema="UserInvitationPagination",
+ *     type="object",
+ *
+ *     @OA\Property(
+ *         property="data",
+ *         type="array",
+ *
+ *         @OA\Items(ref="#/components/schemas/UserInvitation")
+ *     ),
+ *
+ *     @OA\Property(property="current_page", type="integer", example=1),
+ *     @OA\Property(property="last_page", type="integer", example=5),
+ *     @OA\Property(property="per_page", type="integer", example=20),
+ *     @OA\Property(property="total", type="integer", example=100)
+ * )
+ *
+ * @OA\Schema(
+ *     schema="InviteUserRequest",
+ *     type="object",
+ *     required={"email"},
+ *
+ *     @OA\Property(property="email", type="string", format="email", example="newuser@example.com", description="초대할 사용자 이메일"),
+ *     @OA\Property(property="role_id", type="integer", nullable=true, example=2, description="부여할 역할 ID"),
+ *     @OA\Property(property="message", type="string", nullable=true, example="SAM 시스템에 합류해 주세요!", description="초대 메시지"),
+ *     @OA\Property(property="expires_days", type="integer", nullable=true, example=7, minimum=1, maximum=30, description="만료 기간(일)")
+ * )
+ *
+ * @OA\Schema(
+ *     schema="AcceptInvitationRequest",
+ *     type="object",
+ *     required={"name", "password", "password_confirmation"},
+ *
+ *     @OA\Property(property="name", type="string", example="홍길동", description="사용자 이름"),
+ *     @OA\Property(property="password", type="string", format="password", example="password123", description="비밀번호 (8자 이상)"),
+ *     @OA\Property(property="password_confirmation", type="string", format="password", example="password123", description="비밀번호 확인"),
+ *     @OA\Property(property="phone", type="string", nullable=true, example="010-1234-5678", description="연락처")
+ * )
+ */
+class UserInvitationApi
+{
+    /**
+     * @OA\Get(
+     *     path="/api/v1/users/invitations",
+     *     operationId="getUserInvitations",
+     *     tags={"UserInvitation"},
+     *     summary="초대 목록 조회",
+     *     description="테넌트의 사용자 초대 목록을 조회합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Parameter(
+     *         name="status",
+     *         in="query",
+     *         description="상태 필터",
+     *         required=false,
+     *
+     *         @OA\Schema(type="string", enum={"pending", "accepted", "expired", "cancelled"})
+     *     ),
+     *
+     *     @OA\Parameter(
+     *         name="search",
+     *         in="query",
+     *         description="이메일 검색",
+     *         required=false,
+     *
+     *         @OA\Schema(type="string")
+     *     ),
+     *
+     *     @OA\Parameter(
+     *         name="sort_by",
+     *         in="query",
+     *         description="정렬 기준",
+     *         required=false,
+     *
+     *         @OA\Schema(type="string", enum={"created_at", "expires_at", "email"}, default="created_at")
+     *     ),
+     *
+     *     @OA\Parameter(
+     *         name="sort_dir",
+     *         in="query",
+     *         description="정렬 방향",
+     *         required=false,
+     *
+     *         @OA\Schema(type="string", enum={"asc", "desc"}, default="desc")
+     *     ),
+     *
+     *     @OA\Parameter(
+     *         name="per_page",
+     *         in="query",
+     *         description="페이지당 항목 수",
+     *         required=false,
+     *
+     *         @OA\Schema(type="integer", default=20, minimum=1, maximum=100)
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="조회 완료"),
+     *             @OA\Property(property="data", ref="#/components/schemas/UserInvitationPagination")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=403, description="권한 없음")
+     * )
+     */
+    public function index() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/users/invite",
+     *     operationId="inviteUser",
+     *     tags={"UserInvitation"},
+     *     summary="사용자 초대",
+     *     description="새로운 사용자를 테넌트에 초대합니다. 초대 이메일이 발송됩니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/InviteUserRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="초대 발송 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="초대가 발송되었습니다"),
+     *             @OA\Property(property="data", ref="#/components/schemas/UserInvitation")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="이미 가입된 사용자 또는 대기 중인 초대 존재"),
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=422, description="유효성 검증 실패")
+     * )
+     */
+    public function invite() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/users/invitations/{token}/accept",
+     *     operationId="acceptInvitation",
+     *     tags={"UserInvitation"},
+     *     summary="초대 수락",
+     *     description="초대를 수락하고 사용자 계정을 생성합니다. 인증 불필요.",
+     *     security={{"ApiKeyAuth": {}}},
+     *
+     *     @OA\Parameter(
+     *         name="token",
+     *         in="path",
+     *         description="초대 토큰",
+     *         required=true,
+     *
+     *         @OA\Schema(type="string")
+     *     ),
+     *
+     *     @OA\RequestBody(
+     *         required=true,
+     *
+     *         @OA\JsonContent(ref="#/components/schemas/AcceptInvitationRequest")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="초대 수락 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="초대가 수락되었습니다"),
+     *             @OA\Property(property="data", type="object",
+     *                 @OA\Property(property="id", type="integer"),
+     *                 @OA\Property(property="name", type="string"),
+     *                 @OA\Property(property="email", type="string")
+     *             )
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="만료된 초대 또는 잘못된 상태"),
+     *     @OA\Response(response=404, description="초대를 찾을 수 없음"),
+     *     @OA\Response(response=422, description="유효성 검증 실패")
+     * )
+     */
+    public function accept() {}
+
+    /**
+     * @OA\Delete(
+     *     path="/api/v1/users/invitations/{id}",
+     *     operationId="cancelInvitation",
+     *     tags={"UserInvitation"},
+     *     summary="초대 취소",
+     *     description="대기 중인 초대를 취소합니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Parameter(
+     *         name="id",
+     *         in="path",
+     *         description="초대 ID",
+     *         required=true,
+     *
+     *         @OA\Schema(type="integer")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="취소 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="초대가 취소되었습니다"),
+     *             @OA\Property(property="data", type="boolean", example=true)
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="취소할 수 없는 상태"),
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="초대를 찾을 수 없음")
+     * )
+     */
+    public function cancel() {}
+
+    /**
+     * @OA\Post(
+     *     path="/api/v1/users/invitations/{id}/resend",
+     *     operationId="resendInvitation",
+     *     tags={"UserInvitation"},
+     *     summary="초대 재발송",
+     *     description="대기 중인 초대 이메일을 재발송합니다. 만료 기간이 연장됩니다.",
+     *     security={{"ApiKeyAuth": {}}, {"BearerAuth": {}}},
+     *
+     *     @OA\Parameter(
+     *         name="id",
+     *         in="path",
+     *         description="초대 ID",
+     *         required=true,
+     *
+     *         @OA\Schema(type="integer")
+     *     ),
+     *
+     *     @OA\Response(
+     *         response=200,
+     *         description="재발송 성공",
+     *
+     *         @OA\JsonContent(
+     *
+     *             @OA\Property(property="success", type="boolean", example=true),
+     *             @OA\Property(property="message", type="string", example="초대가 재발송되었습니다"),
+     *             @OA\Property(property="data", ref="#/components/schemas/UserInvitation")
+     *         )
+     *     ),
+     *
+     *     @OA\Response(response=400, description="재발송할 수 없는 상태"),
+     *     @OA\Response(response=401, description="인증 실패"),
+     *     @OA\Response(response=404, description="초대를 찾을 수 없음")
+     * )
+     */
+    public function resend() {}
+}
diff --git a/database/migrations/2025_12_18_170000_create_admin_api_deprecations_table.php b/database/migrations/2025_12_18_170000_create_admin_api_deprecations_table.php
index 34d4153..319eb07 100644
--- a/database/migrations/2025_12_18_170000_create_admin_api_deprecations_table.php
+++ b/database/migrations/2025_12_18_170000_create_admin_api_deprecations_table.php
@@ -30,4 +30,4 @@ public function down(): void
     {
         Schema::dropIfExists('admin_api_deprecations');
     }
-};
\ No newline at end of file
+};
diff --git a/database/migrations/2025_12_19_100001_create_user_invitations_table.php b/database/migrations/2025_12_19_100001_create_user_invitations_table.php
new file mode 100644
index 0000000..b51ea8c
--- /dev/null
+++ b/database/migrations/2025_12_19_100001_create_user_invitations_table.php
@@ -0,0 +1,41 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('user_invitations', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('tenant_id')->constrained()->cascadeOnDelete()->comment('테넌트 ID');
+            $table->string('email', 255)->comment('초대 대상 이메일');
+            $table->foreignId('role_id')->nullable()->constrained('roles')->nullOnDelete()->comment('부여할 역할 ID');
+            $table->text('message')->nullable()->comment('초대 메시지');
+            $table->string('token', 64)->unique()->comment('초대 토큰');
+            $table->string('status', 20)->default('pending')->index()->comment('상태 (pending/accepted/expired/cancelled)');
+            $table->foreignId('invited_by')->constrained('users')->cascadeOnDelete()->comment('초대한 사용자 ID');
+            $table->timestamp('expires_at')->comment('만료 일시');
+            $table->timestamp('accepted_at')->nullable()->comment('수락 일시');
+            $table->timestamps();
+
+            // 복합 인덱스: 테넌트별 이메일 검색
+            $table->index(['tenant_id', 'email']);
+            // 복합 인덱스: 상태별 만료 일시 (스케줄러용)
+            $table->index(['status', 'expires_at']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('user_invitations');
+    }
+};
diff --git a/database/migrations/2025_12_19_100002_create_notification_settings_table.php b/database/migrations/2025_12_19_100002_create_notification_settings_table.php
new file mode 100644
index 0000000..33fcaec
--- /dev/null
+++ b/database/migrations/2025_12_19_100002_create_notification_settings_table.php
@@ -0,0 +1,47 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('notification_settings', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('tenant_id')->constrained()->cascadeOnDelete()->comment('테넌트 ID');
+            $table->foreignId('user_id')->constrained()->cascadeOnDelete()->comment('사용자 ID');
+
+            // 알림 유형별 채널 설정
+            $table->string('notification_type', 50)->comment('알림 유형 (approval, order, deposit, withdrawal, notice, system 등)');
+
+            // 채널별 활성화 여부
+            $table->boolean('push_enabled')->default(true)->comment('푸시 알림 활성화');
+            $table->boolean('email_enabled')->default(true)->comment('이메일 알림 활성화');
+            $table->boolean('sms_enabled')->default(false)->comment('SMS 알림 활성화');
+            $table->boolean('in_app_enabled')->default(true)->comment('인앱 알림 활성화');
+            $table->boolean('kakao_enabled')->default(false)->comment('카카오 알림톡 활성화');
+
+            // 추가 설정
+            $table->json('settings')->nullable()->comment('추가 설정 (우선순위, 알림 시간대 등)');
+
+            $table->timestamps();
+
+            // 복합 유니크 인덱스
+            $table->unique(['tenant_id', 'user_id', 'notification_type'], 'notification_settings_unique');
+            $table->index(['user_id', 'notification_type']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('notification_settings');
+    }
+};
diff --git a/lang/ko/error.php b/lang/ko/error.php
index 607ba6b..f478a92 100644
--- a/lang/ko/error.php
+++ b/lang/ko/error.php
@@ -260,4 +260,39 @@
         'invalid_signature' => '서명이 유효하지 않습니다.',
         'token_issue_failed' => '토큰 발급에 실패했습니다.',
     ],
+
+    // 사용자 초대 관련
+    'invitation' => [
+        'already_member' => '이미 테넌트에 등록된 사용자입니다.',
+        'already_pending' => '대기 중인 초대가 이미 존재합니다.',
+        'not_found' => '초대를 찾을 수 없습니다.',
+        'expired' => '만료된 초대입니다.',
+        'invalid_status' => '유효하지 않은 초대 상태입니다.',
+        'cannot_cancel' => '취소할 수 없는 초대입니다.',
+        'cannot_resend' => '재발송할 수 없는 초대입니다.',
+    ],
+
+    // 알림 설정 관련
+    'notification_setting' => [
+        'not_found' => '알림 설정을 찾을 수 없습니다.',
+        'invalid_type' => '유효하지 않은 알림 유형입니다.',
+        'invalid_channel' => '유효하지 않은 알림 채널입니다.',
+    ],
+
+    // 매출 관련
+    'sale' => [
+        'cannot_edit' => '확정된 매출은 수정할 수 없습니다.',
+        'cannot_delete' => '확정된 매출은 삭제할 수 없습니다.',
+        'cannot_confirm' => '확정할 수 없는 상태입니다.',
+        'statement_requires_confirmed' => '확정된 매출만 거래명세서를 발행할 수 있습니다.',
+        'recipient_email_required' => '수신자 이메일이 필요합니다.',
+    ],
+
+    // 계정 관리 관련
+    'account' => [
+        'invalid_password' => '비밀번호가 일치하지 않습니다.',
+        'tenant_membership_not_found' => '테넌트 멤버십 정보를 찾을 수 없습니다.',
+        'already_withdrawn' => '이미 탈퇴한 계정입니다.',
+        'cannot_withdraw' => '탈퇴할 수 없는 상태입니다.',
+    ],
 ];
diff --git a/lang/ko/message.php b/lang/ko/message.php
index ce9c9eb..1fcfa67 100644
--- a/lang/ko/message.php
+++ b/lang/ko/message.php
@@ -270,6 +270,13 @@
         'purchase' => '매입',
     ],
 
+    // 매출 관리
+    'sale' => [
+        'confirmed' => '매출이 확정되었습니다.',
+        'statement_issued' => '거래명세서가 발행되었습니다.',
+        'statement_sent' => '거래명세서가 발송되었습니다.',
+    ],
+
     // 급여 관리
     'payroll' => [
         'fetched' => '급여를 조회했습니다.',
@@ -316,4 +323,27 @@
     'internal' => [
         'token_exchanged' => '토큰이 발급되었습니다.',
     ],
+
+    // 사용자 초대 관리
+    'invitation' => [
+        'sent' => '초대가 발송되었습니다.',
+        'accepted' => '초대가 수락되었습니다.',
+        'cancelled' => '초대가 취소되었습니다.',
+        'resent' => '초대가 재발송되었습니다.',
+    ],
+
+    // 알림 설정 관리
+    'notification_setting' => [
+        'fetched' => '알림 설정을 조회했습니다.',
+        'updated' => '알림 설정이 수정되었습니다.',
+        'bulk_updated' => '알림 설정이 일괄 저장되었습니다.',
+        'initialized' => '알림 설정이 초기화되었습니다.',
+    ],
+
+    // 계정 관리
+    'account' => [
+        'withdrawn' => '회원 탈퇴가 완료되었습니다.',
+        'suspended' => '사용 중지가 완료되었습니다.',
+        'agreements_updated' => '약관 동의 정보가 수정되었습니다.',
+    ],
 ];
diff --git a/routes/api.php b/routes/api.php
index 9406cf6..9b789f2 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -1,6 +1,7 @@
 <?php
 
 use App\Http\Controllers\Api\Admin\GlobalMenuController;
+use App\Http\Controllers\Api\V1\AccountController;
 use App\Http\Controllers\Api\V1\AdminController;
 use App\Http\Controllers\Api\V1\AiReportController;
 use App\Http\Controllers\Api\V1\ApiController;
@@ -38,8 +39,8 @@
 use App\Http\Controllers\Api\V1\ItemMaster\ItemBomItemController;
 use App\Http\Controllers\Api\V1\ItemMaster\ItemFieldController;
 use App\Http\Controllers\Api\V1\ItemMaster\ItemMasterController;
-use App\Http\Controllers\Api\V1\ItemMaster\ItemPageController;
 // use App\Http\Controllers\Api\V1\MaterialController; // REMOVED: materials 테이블 삭제됨
+use App\Http\Controllers\Api\V1\ItemMaster\ItemPageController;
 use App\Http\Controllers\Api\V1\ItemMaster\ItemSectionController;
 use App\Http\Controllers\Api\V1\ItemMaster\SectionTemplateController;
 use App\Http\Controllers\Api\V1\ItemMaster\UnitOptionController;
@@ -50,10 +51,11 @@
 use App\Http\Controllers\Api\V1\LoanController;
 use App\Http\Controllers\Api\V1\MenuController;
 use App\Http\Controllers\Api\V1\ModelSetController;
+use App\Http\Controllers\Api\V1\NotificationSettingController;
 use App\Http\Controllers\Api\V1\PaymentController;
-use App\Http\Controllers\Api\V1\PayrollController;
 // use App\Http\Controllers\Api\V1\ProductBomItemController; // REMOVED: products 테이블 삭제됨
 // use App\Http\Controllers\Api\V1\ProductController; // REMOVED: products 테이블 삭제됨
+use App\Http\Controllers\Api\V1\PayrollController;
 use App\Http\Controllers\Api\V1\PermissionController;
 use App\Http\Controllers\Api\V1\PlanController;
 use App\Http\Controllers\Api\V1\PostController;
@@ -69,16 +71,17 @@
 use App\Http\Controllers\Api\V1\SaleController;
 use App\Http\Controllers\Api\V1\SiteController;
 use App\Http\Controllers\Api\V1\SubscriptionController;
-use App\Http\Controllers\Api\V1\TaxInvoiceController;
 // 설계 전용 (디자인 네임스페이스)
+use App\Http\Controllers\Api\V1\TaxInvoiceController;
 use App\Http\Controllers\Api\V1\TenantController;
 use App\Http\Controllers\Api\V1\TenantFieldSettingController;
 use App\Http\Controllers\Api\V1\TenantOptionGroupController;
 use App\Http\Controllers\Api\V1\TenantOptionValueController;
-use App\Http\Controllers\Api\V1\TenantStatFieldController;
 // 모델셋 관리 (견적 시스템)
+use App\Http\Controllers\Api\V1\TenantStatFieldController;
 use App\Http\Controllers\Api\V1\TenantUserProfileController;
 use App\Http\Controllers\Api\V1\UserController;
+use App\Http\Controllers\Api\V1\UserInvitationController;
 use App\Http\Controllers\Api\V1\UserRoleController;
 use App\Http\Controllers\Api\V1\WithdrawalController;
 use App\Http\Controllers\Api\V1\WorkSettingController;
@@ -154,6 +157,28 @@
 
             Route::get('me/tenants', [UserController::class, 'tenants'])->name('v1.users.me.tenants.index');          // 내 테넌트 목록
             Route::patch('me/tenants/switch', [UserController::class, 'switchTenant'])->name('v1.users.me.tenants.switch');  // 활성 테넌트 전환
+
+            // 사용자 초대 API
+            Route::get('invitations', [UserInvitationController::class, 'index'])->name('v1.users.invitations.index');           // 초대 목록
+            Route::post('invite', [UserInvitationController::class, 'invite'])->name('v1.users.invite');                          // 초대 발송
+            Route::post('invitations/{token}/accept', [UserInvitationController::class, 'accept'])->name('v1.users.invitations.accept'); // 초대 수락
+            Route::delete('invitations/{id}', [UserInvitationController::class, 'cancel'])->whereNumber('id')->name('v1.users.invitations.cancel'); // 초대 취소
+            Route::post('invitations/{id}/resend', [UserInvitationController::class, 'resend'])->whereNumber('id')->name('v1.users.invitations.resend'); // 초대 재발송
+
+            // 알림 설정 API (auth:sanctum 필수)
+            Route::middleware('auth:sanctum')->group(function () {
+                Route::get('me/notification-settings', [NotificationSettingController::class, 'index'])->name('v1.users.me.notification-settings.index'); // 알림 설정 조회
+                Route::put('me/notification-settings', [NotificationSettingController::class, 'update'])->name('v1.users.me.notification-settings.update'); // 알림 설정 수정
+                Route::put('me/notification-settings/bulk', [NotificationSettingController::class, 'bulkUpdate'])->name('v1.users.me.notification-settings.bulk'); // 알림 일괄 설정
+            });
+        });
+
+        // Account API (계정 관리 - 탈퇴, 사용중지, 약관동의)
+        Route::prefix('account')->middleware('auth:sanctum')->group(function () {
+            Route::post('withdraw', [AccountController::class, 'withdraw'])->name('v1.account.withdraw'); // 회원 탈퇴
+            Route::post('suspend', [AccountController::class, 'suspend'])->name('v1.account.suspend'); // 사용 중지 (테넌트)
+            Route::get('agreements', [AccountController::class, 'getAgreements'])->name('v1.account.agreements.index'); // 약관 동의 조회
+            Route::put('agreements', [AccountController::class, 'updateAgreements'])->name('v1.account.agreements.update'); // 약관 동의 수정
         });
 
         // Tenant API
@@ -453,6 +478,10 @@
             Route::put('/{id}', [SaleController::class, 'update'])->whereNumber('id')->name('v1.sales.update');
             Route::delete('/{id}', [SaleController::class, 'destroy'])->whereNumber('id')->name('v1.sales.destroy');
             Route::post('/{id}/confirm', [SaleController::class, 'confirm'])->whereNumber('id')->name('v1.sales.confirm');
+            // 거래명세서 API
+            Route::get('/{id}/statement', [SaleController::class, 'getStatement'])->whereNumber('id')->name('v1.sales.statement.show');
+            Route::post('/{id}/statement/issue', [SaleController::class, 'issueStatement'])->whereNumber('id')->name('v1.sales.statement.issue');
+            Route::post('/{id}/statement/send', [SaleController::class, 'sendStatement'])->whereNumber('id')->name('v1.sales.statement.send');
         });
 
         // Purchase API (매입 관리)