diff --git a/.gitignore b/.gitignore
index 0e945e0..384836e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 bin/
 obj/
 .idea/
+hsntsn.csv
\ No newline at end of file
diff --git a/README.md b/README.md
index bae79b4..31d79e5 100644
--- a/README.md
+++ b/README.md
@@ -2,9 +2,9 @@
 
 .NET console scraper.
 
-Kaynak: `http://www.hsn-tsn.de/`
+Source: `http://www.hsn-tsn.de/`
 
-CSV cikti alanlari:
+CSV output fields:
 
 - `HsnTsn`, `Hsn`, `Tsn`
 - `Brand`, `VehicleType`, `Model`, `OfficialType`
@@ -13,22 +13,22 @@ CSV cikti alanlari:
 - `MatchKey`
 - `SourceQuery`, `SourceListUrl`, `SourceDetailUrl`
 
-## Calistirma
+## Usage
 
-Tum marka sayfalarini tara:
+Scrape all brand pages:
 
 ```bash
 dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj > hsntsn.csv
 ```
 
-Sadece verilen sorgulari tara (`stdin`):
+Scrape only specific queries from `stdin`:
 
 ```bash
 printf "0588\nGolf\n" | dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj > hsntsn.csv
 ```
 
-Detay sayfasi zenginlestirmesini kapat:
+Enable detail-page enrichment:
 
 ```bash
-printf "0588\n" | dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj -- --skip-details
+printf "0588\n" | dotnet run --project src/HsnTsnScraper/HsnTsnScraper.csproj -- --include-details
 ```
diff --git a/src/HsnTsnScraper/Program.cs b/src/HsnTsnScraper/Program.cs
index 3a62c42..588c495 100644
--- a/src/HsnTsnScraper/Program.cs
+++ b/src/HsnTsnScraper/Program.cs
@@ -3,60 +3,14 @@ using CsvHelper;
 using CsvHelper.Configuration;
 using HsnTsnScraper;
 
-var includeDetails = !args.Contains("--skip-details", StringComparer.OrdinalIgnoreCase);
+var includeDetails = args.Contains("--include-details", StringComparer.OrdinalIgnoreCase);
 
 using var client = new HsnTsnClient();
-var map = new Dictionary<string, HsnTsnVehicle>(StringComparer.OrdinalIgnoreCase);
+var written = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+var processed = 0;
+var failed = 0;
 
-if (Console.IsInputRedirected)
-{
-    await foreach (var query in ReadInput())
-    {
-        var vehicles = await client.GetVehiclesFromSearchAsync(query);
-        Merge(map, vehicles);
-    }
-}
-else
-{
-    var brandUrls = await client.GetBrandPageUrls();
-    foreach (var url in brandUrls)
-    {
-        var vehicles = await client.GetVehiclesFromBrandPageAsync(url);
-        Merge(map, vehicles);
-    }
-}
-
-if (includeDetails)
-{
-    foreach (var vehicle in map.Values)
-    {
-        var detail = await client.GetVehicleDetailAsync(vehicle.SourceDetailUrl);
-        if (detail is null)
-        {
-            continue;
-        }
-
-        if (!string.IsNullOrWhiteSpace(detail.Brand))
-        {
-            vehicle.Brand = detail.Brand;
-        }
-
-        vehicle.Model = detail.Model;
-        vehicle.OfficialType = detail.OfficialType;
-        vehicle.YearFrom = detail.YearFrom;
-        vehicle.YearTo = detail.YearTo;
-
-        if (!string.IsNullOrWhiteSpace(detail.CanonicalUrl))
-        {
-            vehicle.SourceDetailUrl = detail.CanonicalUrl;
-        }
-    }
-}
-
-foreach (var vehicle in map.Values)
-{
-    vehicle.MatchKey = BuildMatchKey(vehicle);
-}
+Console.Error.WriteLine($"[info] Scrape started. includeDetails={includeDetails}");
 
 await using var csvWriter = new CsvWriter(Console.Out, new CsvConfiguration(CultureInfo.InvariantCulture)
 {
@@ -65,67 +19,115 @@ await using var csvWriter = new CsvWriter(Console.Out, new CsvConfiguration(Cult
 
 csvWriter.WriteHeader<HsnTsnVehicle>();
 await csvWriter.NextRecordAsync();
-
-foreach (var vehicle in map.Values.OrderBy(x => x.Hsn, StringComparer.OrdinalIgnoreCase).ThenBy(x => x.Tsn, StringComparer.OrdinalIgnoreCase))
-{
-    csvWriter.WriteRecord(vehicle);
-    await csvWriter.NextRecordAsync();
-}
-
 await csvWriter.FlushAsync();
 
-return;
-
-void Merge(IDictionary<string, HsnTsnVehicle> mapByHsnTsn, IEnumerable<HsnTsnVehicle> vehicles)
+if (Console.IsInputRedirected)
 {
-    foreach (var vehicle in vehicles)
+    await foreach (var query in ReadInput())
     {
-        var key = vehicle.HsnTsn;
-        if (!mapByHsnTsn.TryGetValue(key, out var existing))
+        IReadOnlyList<HsnTsnVehicle> vehicles;
+        try
         {
-            mapByHsnTsn[key] = vehicle;
+            vehicles = await client.GetVehiclesFromSearchAsync(query);
+        }
+        catch (Exception ex)
+        {
+            failed++;
+            Console.Error.WriteLine($"[warn] Query failed: {query} -> {ex.Message}");
             continue;
         }
 
-        if (string.IsNullOrWhiteSpace(existing.VehicleType) && !string.IsNullOrWhiteSpace(vehicle.VehicleType))
+        foreach (var vehicle in vehicles)
         {
-            existing.VehicleType = vehicle.VehicleType;
+            await WriteVehicleIfNew(vehicle);
+        }
+    }
+}
+else
+{
+    IReadOnlyList<string> brandUrls;
+    try
+    {
+        brandUrls = await client.GetBrandPageUrls();
+    }
+    catch (Exception ex)
+    {
+        Console.Error.WriteLine($"[error] Could not fetch brand urls: {ex.Message}");
+        return;
+    }
+
+    foreach (var url in brandUrls)
+    {
+        Console.Error.WriteLine($"[info] Processing: {url}");
+        IReadOnlyList<HsnTsnVehicle> vehicles;
+        try
+        {
+            vehicles = await client.GetVehiclesFromBrandPageAsync(url);
+        }
+        catch (Exception ex)
+        {
+            failed++;
+            Console.Error.WriteLine($"[warn] Brand page failed: {url} -> {ex.Message}");
+            continue;
         }
 
-        if (existing.PowerPs is null && vehicle.PowerPs is not null)
+        foreach (var vehicle in vehicles)
         {
-            existing.PowerPs = vehicle.PowerPs;
+            await WriteVehicleIfNew(vehicle);
         }
+    }
+}
 
-        if (existing.PowerKw is null && vehicle.PowerKw is not null)
-        {
-            existing.PowerKw = vehicle.PowerKw;
-        }
+await csvWriter.FlushAsync();
+Console.Error.WriteLine($"[info] Scrape finished. written={written.Count}, processed={processed}, failed={failed}");
+return;
 
-        if (existing.DisplacementCcm is null && vehicle.DisplacementCcm is not null)
-        {
-            existing.DisplacementCcm = vehicle.DisplacementCcm;
-        }
+async Task WriteVehicleIfNew(HsnTsnVehicle vehicle)
+{
+    processed++;
 
-        if (string.IsNullOrWhiteSpace(existing.FuelType) && !string.IsNullOrWhiteSpace(vehicle.FuelType))
-        {
-            existing.FuelType = vehicle.FuelType;
-        }
+    if (!written.Add(vehicle.HsnTsn))
+    {
+        return;
+    }
 
-        if (string.IsNullOrWhiteSpace(existing.SourceQuery) && !string.IsNullOrWhiteSpace(vehicle.SourceQuery))
+    if (includeDetails && !string.IsNullOrWhiteSpace(vehicle.SourceDetailUrl))
+    {
+        try
         {
-            existing.SourceQuery = vehicle.SourceQuery;
-        }
+            var detail = await client.GetVehicleDetailAsync(vehicle.SourceDetailUrl);
+            if (detail is not null)
+            {
+                if (!string.IsNullOrWhiteSpace(detail.Brand))
+                {
+                    vehicle.Brand = detail.Brand;
+                }
 
-        if (string.IsNullOrWhiteSpace(existing.SourceListUrl) && !string.IsNullOrWhiteSpace(vehicle.SourceListUrl))
-        {
-            existing.SourceListUrl = vehicle.SourceListUrl;
-        }
+                vehicle.Model = detail.Model;
+                vehicle.OfficialType = detail.OfficialType;
+                vehicle.YearFrom = detail.YearFrom;
+                vehicle.YearTo = detail.YearTo;
 
-        if (string.IsNullOrWhiteSpace(existing.SourceDetailUrl) && !string.IsNullOrWhiteSpace(vehicle.SourceDetailUrl))
-        {
-            existing.SourceDetailUrl = vehicle.SourceDetailUrl;
+                if (!string.IsNullOrWhiteSpace(detail.CanonicalUrl))
+                {
+                    vehicle.SourceDetailUrl = detail.CanonicalUrl;
+                }
+            }
         }
+        catch (Exception ex)
+        {
+            failed++;
+            Console.Error.WriteLine($"[warn] Detail failed: {vehicle.HsnTsn} -> {ex.Message}");
+        }
+    }
+
+    vehicle.MatchKey = BuildMatchKey(vehicle);
+    csvWriter.WriteRecord(vehicle);
+    await csvWriter.NextRecordAsync();
+
+    if (written.Count % 250 == 0)
+    {
+        await csvWriter.FlushAsync();
     }
 }