I already have a fully working Python + PySide6 (Qt) desktop application that scans UPCs, fetches fake offers, and reprices my Amazon FBM inventory using my exact rules. The pricing engine, GUI, configuration system, batching, throttling controls, and fake API are all complete. I need the remaining 20–30 percent finished to connect the app to the real Amazon SP-API and finalize persistence and polish. Project summary: The app reads my current inventory (TSV/CSV) and reprices items based on total price to customer (item + shipping). It can also add new listings by scanning UPC → ASIN → computed price → Excel upload. Pricing logic, min/max rules, token-bucket rate limiting, exponential back-off, and batching are already implemented. Work required: SP-API integration • Catalog Items API: UPC → ASIN (with title, image, artist). • Product Pricing (Batch): retrieve competitive offers (price + shipping). • Implement authentication, handle 429 / 503 throttles using exponential back-off, respect Amazon rate-limit headers. SQLite persistence • Cache UPC↔ASIN lookups. • Store protected SKUs and custom min/max overrides. UI and workflow improvements • Progress bar for repricing batches. • Display thumbnails in multi-ASIN selection. • Keyboard navigation and minor layout cleanup. Final testing with my real inventory and Excel loader format. Tech stack (already implemented): Python 3.11, PySide6 (Qt GUI), pandas, openpyxl, YAML config. Modules: fbm_tool/pricing.py, spapi_client.py, io_loader.py, app.py, utils.py. Provided materials: Complete working project ZIP (runs locally with Fake SP-API). Sample inventory and loader Excel files. Amazon SP-API credentials. Exact pricing rules already implemented. Deliverables: Working integration with live Amazon data (UPC → ASIN → offers). Updated Excel/TSV outputs identical in structure to current fake-data runs. SQLite caching and persistence. Clean, maintainable, fully documented code. Developer requirements: Proven experience with Amazon SP-API (Catalog Items + Product Pricing). Solid Python programming skills (async, requests, or boto3-style HTTP work). Experience with PyQt / PySide, pandas, openpyxl. Prior work on Amazon listing or repricing tools preferred. Implementation details already built in: Batch repricing (default 25 ASINs per batch). Token-bucket rate limiting and exponential back-off with jitter. Configurable delay between batches (default 0.75 seconds). Logging for throttles and retries. Editable YAML configuration for all parameters. Ownership and maintenance: Full source code and build instructions must be delivered. I will retain complete rights to the code for future maintenance. Include a 60-day warranty period for small bug fixes after delivery. Application instructions: Start your bid with “I’ve built SP-API tools before.” Include one or two examples of Amazon-related projects or repositories you’ve completed.