diff --git a/tests/features/PurchaseTicketsTest.php b/tests/features/PurchaseTicketsTest.php
index a947a7e..3edc82d 100644
--- a/tests/features/PurchaseTicketsTest.php
+++ b/tests/features/PurchaseTicketsTest.php
@@ -18,6 +18,17 @@ class PurchaseTicketsTest extends TestCase
         $this->app->instance(PaymentGateway::class, $this->paymentGateway);
     }
 
+    private function orderTickets($concert, $params)
+    {
+        $this->json('POST', "/concerts/{$concert->id}/orders", $params);
+    }
+
+    private function assertValidationError($field)
+    {
+        $this->assertResponseStatus(422);
+        $this->assertArrayHasKey($field, $this->decodeResponseJson());
+    }
+
     /** @test */
     function customer_can_purchase_concert_tickets()
     {
@@ -25,7 +36,7 @@ class PurchaseTicketsTest extends TestCase
         $concert = factory(Concert::class)->create(['ticket_price' => 3250]);
 
         // Act
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'email' => 'john@example.com',
             'ticket_quantity' => 3,
             'payment_token' => $this->paymentGateway->getValidTestToken(),
@@ -46,13 +57,12 @@ class PurchaseTicketsTest extends TestCase
     {
         $concert = factory(Concert::class)->create();
 
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'ticket_quantity' => 3,
             'payment_token' => $this->paymentGateway->getValidTestToken(),
         ]);
 
-        $this->assertResponseStatus(422);
-        $this->assertArrayHasKey('email', $this->decodeResponseJson());
+        $this->assertValidationError('email');
     }
 
     /** @test */
@@ -60,14 +70,13 @@ class PurchaseTicketsTest extends TestCase
     {
         $concert = factory(Concert::class)->create();
 
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'email' => 'not-an-email-address',
             'ticket_quantity' => 3,
             'payment_token' => $this->paymentGateway->getValidTestToken(),
         ]);
 
-        $this->assertResponseStatus(422);
-        $this->assertArrayHasKey('email', $this->decodeResponseJson());
+        $this->assertValidationError('email');
     }
 
     /** @test */
@@ -75,13 +84,12 @@ class PurchaseTicketsTest extends TestCase
     {
         $concert = factory(Concert::class)->create();
 
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'email' => 'john@example.com',
             'payment_token' => $this->paymentGateway->getValidTestToken(),
         ]);
 
-        $this->assertResponseStatus(422);
-        $this->assertArrayHasKey('ticket_quantity', $this->decodeResponseJson());
+        $this->assertValidationError('ticket_quantity');
     }
 
     /** @test */
@@ -89,14 +97,13 @@ class PurchaseTicketsTest extends TestCase
     {
         $concert = factory(Concert::class)->create();
 
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'email' => 'john@example.com',
             'ticket_quantity' => 0,
             'payment_token' => $this->paymentGateway->getValidTestToken(),
         ]);
 
-        $this->assertResponseStatus(422);
-        $this->assertArrayHasKey('ticket_quantity', $this->decodeResponseJson());
+        $this->assertValidationError('ticket_quantity');
     }
 
     /** @test */
@@ -104,12 +111,11 @@ class PurchaseTicketsTest extends TestCase
     {
         $concert = factory(Concert::class)->create();
 
-        $this->json('POST', "/concerts/{$concert->id}/orders", [
+        $this->orderTickets($concert, [
             'email' => 'john@example.com',
             'ticket_quantity' => 3,
         ]);
 
-        $this->assertResponseStatus(422);
-        $this->assertArrayHasKey('payment_token', $this->decodeResponseJson());
+        $this->assertValidationError('payment_token');
     }
 }