diff --git a/tests/Controller/Api/ApiExpenseControllerTrait.php b/tests/Controller/Api/ApiExpenseControllerTrait.php
new file mode 100644
index 0000000..57563fa
--- /dev/null
+++ b/tests/Controller/Api/ApiExpenseControllerTrait.php
@@ -0,0 +1,86 @@
+<?php
+/**
+ * Jingga
+ *
+ * PHP Version 8.1
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 2.0
+ * @version   1.0.0
+ * @link      https://jingga.app
+ */
+declare(strict_types=1);
+
+namespace Modules\BusinessExpenses\tests\Controller\Api;
+
+use phpOMS\Account\AccountStatus;
+use phpOMS\Account\AccountType;
+use phpOMS\Message\Http\HttpRequest;
+use phpOMS\Message\Http\HttpResponse;
+use phpOMS\Message\Http\RequestStatusCode;
+use phpOMS\System\File\Local\Directory;
+use phpOMS\Uri\HttpUri;
+use phpOMS\Utils\RnG\DateTime;
+use phpOMS\Utils\TestUtils;
+
+trait ApiExpenseControllerTrait
+{
+    public function testExpenseCreate() : void
+    {
+        $response = new HttpResponse();
+        $request  = new HttpRequest(new HttpUri(''));
+
+        $request->header->account = 1;
+        $request->setData('type', 1);
+        $request->setData('description', 'Some test description');
+
+        $this->module->apiExpenseCreate($request, $response);
+        self::assertEquals('ok', $response->getData('')['status']);
+        self::assertGreaterThan(0, $response->getDataArray('')['response']->id);
+    }
+
+    public function testExpenseElementCreate() : void
+    {
+        if (!\is_dir(__DIR__ . '/temp')) {
+            \mkdir(__DIR__ . '/temp');
+        }
+
+        $response = new HttpResponse();
+        $request  = new HttpRequest(new HttpUri(''));
+
+        $request->header->account = 1;
+
+        $request->setData('type', 1);
+        $request->setData('description', 'Test description');
+        $request->setData('expense', 1);
+
+        $tmpInvoices = \scandir(__DIR__ . '/billing');
+        $invoiceDocs = [];
+        foreach ($tmpInvoices as $invoice) {
+            if ($invoice !== '..' && $invoice !== '.') {
+                $invoiceDocs[] = $invoice;
+            }
+        }
+
+        $file = $invoiceDocs[0];
+        \copy(__DIR__ . '/billing/' . $file, __DIR__ . '/temp/' . $file);
+
+        $toUpload['file0'] = [
+            'name'     => $file,
+            'type'     => \explode('.', $file)[1],
+            'tmp_name' => __DIR__ . '/temp/' . $file,
+            'error'    => \UPLOAD_ERR_OK,
+            'size'     => \filesize(__DIR__ . '/temp/' . $file),
+        ];
+
+        TestUtils::setMember($request, 'files', $toUpload);
+        $this->module->apiExpenseElementCreate($request, $response);
+        self::assertEquals('ok', $response->getData('')['status']);
+        self::assertGreaterThan(0, $response->getDataArray('')['response']->id);
+
+        if (\is_dir(__DIR__ . '/temp')) {
+            Directory::delete(__DIR__ . '/temp');
+        }
+    }
+}
diff --git a/tests/Controller/Api/billing/Invoice # INV0041-1-text.pdf b/tests/Controller/Api/billing/Invoice # INV0041-1-text.pdf
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index 0000000..99506f7
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diff --git a/tests/Controller/Api/billing/Invoice - INV0041-1-image.pdf b/tests/Controller/Api/billing/Invoice - INV0041-1-image.pdf
new file mode 100644
index 0000000..10a3a94
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diff --git a/tests/Controller/ApiControllerTest.php b/tests/Controller/ApiControllerTest.php
new file mode 100644
index 0000000..d9e6027
--- /dev/null
+++ b/tests/Controller/ApiControllerTest.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * Jingga
+ *
+ * PHP Version 8.1
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 2.0
+ * @version   1.0.0
+ * @link      https://jingga.app
+ */
+declare(strict_types=1);
+
+namespace Modules\BusinessExpenses\tests\Controller;
+
+use Model\CoreSettings;
+use Modules\Admin\Models\AccountPermission;
+use Modules\BusinessExpenses\tests\Controller\Api\ApiExpenseControllerTrait;
+use phpOMS\Account\Account;
+use phpOMS\Account\AccountManager;
+use phpOMS\Account\PermissionType;
+use phpOMS\Application\ApplicationAbstract;
+use phpOMS\Dispatcher\Dispatcher;
+use phpOMS\Event\EventManager;
+use phpOMS\Localization\L11nManager;
+use phpOMS\Module\ModuleAbstract;
+use phpOMS\Module\ModuleManager;
+use phpOMS\Router\WebRouter;
+use phpOMS\Utils\TestUtils;
+
+/**
+ * @testdox Modules\tests\BusinessExpenses\Controller\ApiControllerTest: BusinessExpenses api controller
+ *
+ * @internal
+ */
+final class ApiControllerTest extends \PHPUnit\Framework\TestCase
+{
+    protected ApplicationAbstract $app;
+
+    /**
+     * @var \Modules\BusinessExpenses\Controller\ApiController
+     */
+    protected ModuleAbstract $module;
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function setUp() : void
+    {
+        $this->app = new class() extends ApplicationAbstract
+        {
+            protected string $appName = 'Api';
+        };
+
+        $this->app->dbPool          = $GLOBALS['dbpool'];
+        $this->app->unitId          = 1;
+        $this->app->accountManager  = new AccountManager($GLOBALS['session']);
+        $this->app->appSettings     = new CoreSettings();
+        $this->app->moduleManager   = new ModuleManager($this->app, __DIR__ . '/../../../../Modules/');
+        $this->app->dispatcher      = new Dispatcher($this->app);
+        $this->app->eventManager    = new EventManager($this->app->dispatcher);
+        $this->app->l11nManager     = new L11nManager();
+        $this->app->eventManager->importFromFile(__DIR__ . '/../../../../Web/Api/Hooks.php');
+
+        $account = new Account();
+        TestUtils::setMember($account, 'id', 1);
+
+        $permission       = new AccountPermission();
+        $permission->unit = 1;
+        $permission->app  = 2;
+        $permission->setPermission(
+            PermissionType::READ
+            | PermissionType::CREATE
+            | PermissionType::MODIFY
+            | PermissionType::DELETE
+            | PermissionType::PERMISSION
+        );
+
+        $account->addPermission($permission);
+
+        $this->app->accountManager->add($account);
+        $this->app->router = new WebRouter();
+
+        $this->module = $this->app->moduleManager->get('BusinessExpenses', 'Api');
+
+        TestUtils::setMember($this->module, 'app', $this->app);
+    }
+
+    use ApiExpenseControllerTrait;
+}