Voice-Activated Inventory Software Development

I need a custom stock-inventory system that I can run for life without any recurring subscription fees. The application must work on both Windows PCs and Android phones and let me manage an unlimited number of items entirely through voice commands.

Core workflow I want:
• Speak to add a new item, update its quantity, or ask the system to generate reports.
• See changes reflected instantly across PC and phone thanks to real-time syncing.
• Scan barcodes with the phone camera or a USB scanner on the PC to speed up data entry.
• View clear analytics—stock on hand, fast-moving items, out-of-stock alerts—through an easy dashboard.

Key acceptance criteria
1. Windows desktop app (offline-first, with optional cloud sync for the phone).
2. Android app or PWA that mirrors all desktop functions.
3. Reliable voice recognition in English for the three commands above, with the option to expand later.
4. Unlimited SKUs without performance slow-downs.
5. One-time licence build. I do not want a SaaS product or any per-user limits.
6. Source code, installable executables/APKs, and brief user documentation delivered at hand-off.

I’m open to the tech stack—Python, .NET, Flutter, React Native, or anything you can justify—as long as it meets the criteria above and remains maintainable. If this sounds like a fit, tell me how you’ll approach the voice layer, barcode integration, and cross-platform sync, plus a rough delivery timeline.