diff --git a/Vonage.Test/VerifyV2/StartVerification/RequestBuilderTest.cs b/Vonage.Test/VerifyV2/StartVerification/RequestBuilderTest.cs
index 299d0957..6baeef19 100644
--- a/Vonage.Test/VerifyV2/StartVerification/RequestBuilderTest.cs
+++ b/Vonage.Test/VerifyV2/StartVerification/RequestBuilderTest.cs
@@ -1,4 +1,7 @@
-using FluentAssertions;
+#region
+using FluentAssertions;
+using FsCheck;
+using FsCheck.Xunit;
 using Vonage.Common.Failures;
 using Vonage.Common.Monads;
 using Vonage.Test.Common.Extensions;
@@ -10,6 +13,7 @@
 using Vonage.VerifyV2.StartVerification.WhatsApp;
 using Vonage.VerifyV2.StartVerification.WhatsAppInteractive;
 using Xunit;
+#endregion
 
 namespace Vonage.Test.VerifyV2.StartVerification;
 
@@ -50,21 +54,25 @@ public void Create_ShouldReturnFailure_GivenBrandExceeds16Characters() =>
 
     [Fact]
     public void Create_ShouldReturnFailure_GivenChannelTimeoutIsHigherThanMaximum() =>
-        BuildBaseRequest()
-            .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
-            .WithChannelTimeout(901)
-            .Create()
-            .Should()
-            .BeParsingFailure("ChannelTimeout cannot be higher than 900.");
-
-    [Fact]
-    public void Create_ShouldReturnFailure_GivenChannelTimeoutIsLowerThanMinimum() =>
-        BuildBaseRequest()
-            .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
-            .WithChannelTimeout(59)
-            .Create()
-            .Should()
-            .BeParsingFailure("ChannelTimeout cannot be lower than 60.");
+        Prop.ForAll(
+            GetChannelTimeoutsAboveMaximum(),
+            invalidTimeout => BuildBaseRequest()
+                .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
+                .WithChannelTimeout(invalidTimeout)
+                .Create()
+                .Should()
+                .BeParsingFailure("ChannelTimeout cannot be higher than 900."));
+
+    [Property]
+    public Property Create_ShouldReturnFailure_GivenChannelTimeoutIsLowerThanMinimum() =>
+        Prop.ForAll(
+            GetChannelTimeoutsBelowMinimum(),
+            invalidTimeout => BuildBaseRequest()
+                .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
+                .WithChannelTimeout(invalidTimeout)
+                .Create()
+                .Should()
+                .BeParsingFailure("ChannelTimeout cannot be lower than 15."));
 
     [Fact]
     public void Create_ShouldReturnFailure_GivenCodeLengthIsHigherThanMaximum() =>
@@ -106,17 +114,26 @@ public void Create_ShouldSetBrand() =>
             .Should()
             .BeSuccess("Brand Custom 123");
 
-    [Theory]
-    [InlineData(60)]
-    [InlineData(900)]
-    public void Create_ShouldSetChannelTimeout(int value) =>
-        BuildBaseRequest()
-            .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
-            .WithChannelTimeout(value)
-            .Create()
-            .Map(request => request.ChannelTimeout)
-            .Should()
-            .BeSuccess(value);
+    [Property]
+    public Property Create_ShouldSetChannelTimeout() =>
+        Prop.ForAll(
+            GetValidChannelTimeouts(),
+            validTimeout => BuildBaseRequest()
+                .WithWorkflow(EmailWorkflow.Parse(ValidEmail))
+                .WithChannelTimeout(validTimeout)
+                .Create()
+                .Map(request => request.ChannelTimeout)
+                .Should()
+                .BeSuccess(validTimeout));
+
+    private static Arbitrary<int> GetChannelTimeoutsAboveMaximum() =>
+        Gen.Choose(901, int.MaxValue).ToArbitrary();
+
+    private static Arbitrary<int> GetChannelTimeoutsBelowMinimum() =>
+        Gen.Choose(14, -int.MaxValue).ToArbitrary();
+
+    private static Arbitrary<int> GetValidChannelTimeouts() =>
+        Gen.Choose(15, 900).ToArbitrary();
 
     [Fact]
     public void Create_ShouldSetClientReference() =>
diff --git a/Vonage/VerifyV2/StartVerification/StartVerificationRequestBuilder.cs b/Vonage/VerifyV2/StartVerification/StartVerificationRequestBuilder.cs
index 132257a0..fd369d12 100644
--- a/Vonage/VerifyV2/StartVerification/StartVerificationRequestBuilder.cs
+++ b/Vonage/VerifyV2/StartVerification/StartVerificationRequestBuilder.cs
@@ -1,8 +1,10 @@
+#region
 using System.Collections.Generic;
 using Vonage.Common.Client;
 using Vonage.Common.Failures;
 using Vonage.Common.Monads;
 using Vonage.Common.Validation;
+#endregion
 
 namespace Vonage.VerifyV2.StartVerification;
 
@@ -12,6 +14,12 @@ internal class StartVerificationRequestBuilder :
     IBuilderForWorkflow
 {
     private const int MaxBrandLength = 16;
+
+    private const int MinChannelTimeout = 15;
+    private const int MaxChannelTimeout = 900;
+
+    private const int MinCodeLength = 4;
+    private const int MaxCodeLength = 10;
     private readonly List<IVerificationWorkflow> workflows = new List<IVerificationWorkflow>();
     private string brand;
     private int channelTimeout = 300;
@@ -138,22 +146,23 @@ private static Result<StartVerificationRequest> VerifyBrandLength(
     private static Result<StartVerificationRequest> VerifyChannelTimeoutHigherThanMinimum(
         StartVerificationRequest request) =>
         InputValidation
-            .VerifyHigherOrEqualThan(request, request.ChannelTimeout, 60, nameof(request.ChannelTimeout));
+            .VerifyHigherOrEqualThan(request, request.ChannelTimeout, MinChannelTimeout,
+                nameof(request.ChannelTimeout));
 
     private static Result<StartVerificationRequest> VerifyChannelTimeoutLowerThanMaximum(
         StartVerificationRequest request) =>
         InputValidation
-            .VerifyLowerOrEqualThan(request, request.ChannelTimeout, 900, nameof(request.ChannelTimeout));
+            .VerifyLowerOrEqualThan(request, request.ChannelTimeout, MaxChannelTimeout, nameof(request.ChannelTimeout));
 
     private static Result<StartVerificationRequest> VerifyCodeLengthHigherThanMinimum(
         StartVerificationRequest request) =>
         InputValidation
-            .VerifyHigherOrEqualThan(request, request.CodeLength, 4, nameof(request.CodeLength));
+            .VerifyHigherOrEqualThan(request, request.CodeLength, MinCodeLength, nameof(request.CodeLength));
 
     private static Result<StartVerificationRequest> VerifyCodeLengthLowerThanMaximum(
         StartVerificationRequest request) =>
         InputValidation
-            .VerifyLowerOrEqualThan(request, request.CodeLength, 10, nameof(request.CodeLength));
+            .VerifyLowerOrEqualThan(request, request.CodeLength, MaxCodeLength, nameof(request.CodeLength));
 }
 
 /// <summary>