Multi-Platform Accounting ERP Software Development

I'm looking to develop a comprehensive, multi-user, accounting ERP software. It should be compatible with all Android systems, Windows, and iOS, and work both online and offline.

Key Features:
- A robust inventory management system, including:
- Stock tracking
- Order management
- Supplier management
- All accounting features
- Barcode integration
- Scanning capabilities for sale and purchase
- Online and offline functionality

The software should be primarily optimized for Android systems, though it must also be fully compatible with Windows and iOS.

Ideal Skills and Experience:
- Extensive experience in developing multi-platform software
- Proficient in ERP and accounting software development
- Familiar with inventory management systems
- Skills in integrating barcode and scanning capabilities
- Understands the nuances of offline and online software functionality

I'm willing to invest between 15,000 to 20,000 for this project.