diff --git a/SeaHavenIndustries.Tests/LifecycleStatusMapperTests.cs b/SeaHavenIndustries.Tests/LifecycleStatusMapperTests.cs
new file mode 100644
index 0000000..cd763f4
--- /dev/null
+++ b/SeaHavenIndustries.Tests/LifecycleStatusMapperTests.cs
@@ -0,0 +1,39 @@
+using Data.SeaHavenIndustries.Enums;
+using SeaHaven.Services.Helpers;
+
+namespace SeaHavenIndustries.Tests;
+
+public class LifecycleStatusMapperTests
+{
+    [Theory]
+    [InlineData("Open", LifecycleStatus.Incomplete)]
+    [InlineData("Incomplete", LifecycleStatus.Incomplete)]
+    [InlineData("InProgress", LifecycleStatus.InProgress)]
+    [InlineData("In Progress", LifecycleStatus.InProgress)]
+    [InlineData("Completed", LifecycleStatus.Completed)]
+    [InlineData("Cancelled", LifecycleStatus.Canceled)]
+    [InlineData("On Hold", LifecycleStatus.Pending)]
+    [InlineData("Scheduled", LifecycleStatus.Scheduled)]
+    [InlineData("En Route", LifecycleStatus.EnRoute)]
+    [InlineData("Pending Quote", LifecycleStatus.PendingQuote)]
+    public void FromLegacyStatus_MapsKnownValues(string input, LifecycleStatus expected)
+    {
+        var result = LifecycleStatusMapper.FromLegacyStatus(input);
+        Assert.Equal(expected, result);
+    }
+
+    [Fact]
+    public void FromLegacyStatus_Unknown_ReturnsIncomplete()
+    {
+        var result = LifecycleStatusMapper.FromLegacyStatus("MysteryStatus");
+        Assert.Equal(LifecycleStatus.Incomplete, result);
+    }
+
+    [Theory]
+    [InlineData(LifecycleStatus.EnRoute, "En Route")]
+    [InlineData(LifecycleStatus.PendingQuote, "Pending Quote")]
+    public void ToFeLabel_ReturnsBoardLabel(LifecycleStatus status, string expected)
+    {
+        Assert.Equal(expected, LifecycleStatusMapper.ToFeLabel(status));
+    }
+}
diff --git a/SeaHavenIndustries.Tests/SeaHavenIndustries.Tests.csproj b/SeaHavenIndustries.Tests/SeaHavenIndustries.Tests.csproj
new file mode 100644
index 0000000..5eb8d5d
--- /dev/null
+++ b/SeaHavenIndustries.Tests/SeaHavenIndustries.Tests.csproj
@@ -0,0 +1,28 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="coverlet.collector" Version="6.0.2" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="8.0.8" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="xunit" Version="2.9.2" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="Xunit" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Api.SeaHavenIndustries\Api.SeaHavenIndustries.csproj" />
+    <ProjectReference Include="..\SeaHaven.Services\SeaHaven.Services.csproj" />
+    <ProjectReference Include="..\Data.SeaHavenIndustries\Data.SeaHavenIndustries.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/SeaHavenIndustries.Tests/SyncFieldMergePolicyTests.cs b/SeaHavenIndustries.Tests/SyncFieldMergePolicyTests.cs
new file mode 100644
index 0000000..e88f262
--- /dev/null
+++ b/SeaHavenIndustries.Tests/SyncFieldMergePolicyTests.cs
@@ -0,0 +1,78 @@
+using Data.SeaHavenIndustries;
+using Microsoft.EntityFrameworkCore;
+using SeaHaven.Services.Implementation;
+using SeaHaven.Services.Interfaces;
+
+namespace SeaHavenIndustries.Tests;
+
+public class SyncFieldMergePolicyTests
+{
+    private static ApplicationDbContext CreateContext()
+    {
+        var options = new DbContextOptionsBuilder<ApplicationDbContext>()
+            .UseInMemoryDatabase(Guid.NewGuid().ToString())
+            .Options;
+        return new ApplicationDbContext(options);
+    }
+
+    [Fact]
+    public async Task TryApply_WhenFieldLocked_RejectsAndAudits()
+    {
+        await using var context = CreateContext();
+        var wo = new WorkOrder { Id = 10, Description = "SHOC edited", Status = "Open" };
+        context.workOrders.Add(wo);
+        context.WorkOrderFieldLocks.Add(new WorkOrderFieldLock
+        {
+            WorkOrderId = 10,
+            FieldName = "Description",
+            LockedAt = DateTime.UtcNow
+        });
+        await context.SaveChangesAsync();
+
+        var locks = new WorkOrderFieldLockService(context);
+        var audit = new WorkOrderAuditService(context, locks);
+        var policy = new SyncFieldMergePolicy(locks, audit);
+
+        var syncContext = new WorkOrderSyncContext
+        {
+            WorkOrder = wo,
+            FieldLocks = locks,
+            Audit = audit
+        };
+
+        var applied = await policy.TryApplyAsync(syncContext, "Description", "Sync value");
+
+        Assert.False(applied);
+        Assert.Equal("SHOC edited", wo.Description);
+
+        var logs = await context.WorkOrderAuditLogs.ToListAsync();
+        Assert.Single(logs);
+        Assert.Equal("SyncRejected", logs[0].Action);
+        Assert.Equal("Sync", logs[0].EventType);
+    }
+
+    [Fact]
+    public async Task TryApply_WhenFieldNotLocked_AppliesValue()
+    {
+        await using var context = CreateContext();
+        var wo = new WorkOrder { Id = 11, Description = "Original" };
+        context.workOrders.Add(wo);
+        await context.SaveChangesAsync();
+
+        var locks = new WorkOrderFieldLockService(context);
+        var audit = new WorkOrderAuditService(context, locks);
+        var policy = new SyncFieldMergePolicy(locks, audit);
+
+        var syncContext = new WorkOrderSyncContext
+        {
+            WorkOrder = wo,
+            FieldLocks = locks,
+            Audit = audit
+        };
+
+        var applied = await policy.TryApplyAsync(syncContext, "Description", "From sync");
+
+        Assert.True(applied);
+        Assert.Equal("From sync", wo.Description);
+    }
+}
diff --git a/SeaHavenIndustries.Tests/WorkOrderAuditServiceTests.cs b/SeaHavenIndustries.Tests/WorkOrderAuditServiceTests.cs
new file mode 100644
index 0000000..f3058c3
--- /dev/null
+++ b/SeaHavenIndustries.Tests/WorkOrderAuditServiceTests.cs
@@ -0,0 +1,55 @@
+using Data.SeaHavenIndustries;
+using Data.SeaHavenIndustries.Enums;
+using Microsoft.EntityFrameworkCore;
+using SeaHaven.Services.Implementation;
+using SeaHaven.Services.Interfaces;
+
+namespace SeaHavenIndustries.Tests;
+
+public class WorkOrderAuditServiceTests
+{
+    private static ApplicationDbContext CreateContext()
+    {
+        var options = new DbContextOptionsBuilder<ApplicationDbContext>()
+            .UseInMemoryDatabase(Guid.NewGuid().ToString())
+            .Options;
+        return new ApplicationDbContext(options);
+    }
+
+    [Fact]
+    public async Task LogStatusChanged_CreatesSingleAuditWithManualEventType()
+    {
+        await using var context = CreateContext();
+        context.workOrders.Add(new WorkOrder { Id = 1, Status = "Open" });
+        await context.SaveChangesAsync();
+
+        var locks = new WorkOrderFieldLockService(context);
+        var audit = new WorkOrderAuditService(context, locks);
+
+        await audit.LogStatusChangedAsync(1, "Open", "In Progress", "user-1");
+
+        var logs = await context.WorkOrderAuditLogs.ToListAsync();
+        Assert.Single(logs);
+        Assert.Equal("StatusChanged", logs[0].Action);
+        Assert.Equal("Manual", logs[0].EventType);
+        Assert.Equal("Dispatcher", logs[0].ActorType);
+        Assert.Equal("LifecycleStatus", logs[0].FieldName);
+    }
+
+    [Fact]
+    public async Task LogStatusChanged_CreatesFieldLock()
+    {
+        await using var context = CreateContext();
+        context.workOrders.Add(new WorkOrder { Id = 2, Status = "Open" });
+        await context.SaveChangesAsync();
+
+        var locks = new WorkOrderFieldLockService(context);
+        var audit = new WorkOrderAuditService(context, locks);
+
+        await audit.LogStatusChangedAsync(2, "Open", "Scheduled", "user-1");
+
+        var fieldLocks = await context.WorkOrderFieldLocks.ToListAsync();
+        Assert.Single(fieldLocks);
+        Assert.Equal("LifecycleStatus", fieldLocks[0].FieldName);
+    }
+}
diff --git a/SeaHavenIndustries.Tests/WorkOrderNumberNormalizerTests.cs b/SeaHavenIndustries.Tests/WorkOrderNumberNormalizerTests.cs
new file mode 100644
index 0000000..dcc4755
--- /dev/null
+++ b/SeaHavenIndustries.Tests/WorkOrderNumberNormalizerTests.cs
@@ -0,0 +1,43 @@
+using SeaHaven.Services.Helpers;
+
+namespace SeaHavenIndustries.Tests;
+
+public class WorkOrderNumberNormalizerTests
+{
+    [Fact]
+    public void TryNormalize_PadsToElevenDigits()
+    {
+        var ok = WorkOrderNumberNormalizer.TryNormalize("12345", out var normalized, out var error);
+
+        Assert.True(ok);
+        Assert.Null(error);
+        Assert.Equal("00000012345", normalized);
+    }
+
+    [Fact]
+    public void TryNormalize_AcceptsElevenDigits()
+    {
+        var ok = WorkOrderNumberNormalizer.TryNormalize("10000000001", out var normalized, out _);
+
+        Assert.True(ok);
+        Assert.Equal("10000000001", normalized);
+    }
+
+    [Fact]
+    public void TryNormalize_RejectsEmpty()
+    {
+        var ok = WorkOrderNumberNormalizer.TryNormalize("", out _, out var error);
+
+        Assert.False(ok);
+        Assert.NotNull(error);
+    }
+
+    [Fact]
+    public void TryNormalize_RejectsTooLong()
+    {
+        var ok = WorkOrderNumberNormalizer.TryNormalize("123456789012", out _, out var error);
+
+        Assert.False(ok);
+        Assert.Contains("11", error);
+    }
+}
diff --git a/SeaHavenIndustries.sln b/SeaHavenIndustries.sln
index 429aed6..c814615 100644
--- a/SeaHavenIndustries.sln
+++ b/SeaHavenIndustries.sln
@@ -17,6 +17,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Api.SeaHavenIndustries.Test
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SeaHaven.Services.Tests", "SeaHaven.Services.Tests\SeaHaven.Services.Tests.csproj", "{97455198-C479-47F2-8BC8-601B335DFFAB}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SeaHavenIndustries.Tests", "SeaHavenIndustries.Tests\SeaHavenIndustries.Tests.csproj", "{0093B3F5-0180-4C02-A088-6A564E06CEBF}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -51,6 +53,10 @@ Global
 		{97455198-C479-47F2-8BC8-601B335DFFAB}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{97455198-C479-47F2-8BC8-601B335DFFAB}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{97455198-C479-47F2-8BC8-601B335DFFAB}.Release|Any CPU.Build.0 = Release|Any CPU
+		{0093B3F5-0180-4C02-A088-6A564E06CEBF}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{0093B3F5-0180-4C02-A088-6A564E06CEBF}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{0093B3F5-0180-4C02-A088-6A564E06CEBF}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{0093B3F5-0180-4C02-A088-6A564E06CEBF}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE