Windows Desktop Billing Software Development

I'm looking for a skilled developer to create a billing software for Windows desktop. The software should include the following main features:

- Invoice Generation: Create and customize invoices.
- Customer Database: Maintain a comprehensive customer information database.
- Payment Tracking: Monitor and track payments.

Ideal skills and experience:
- Proficiency in desktop application development, especially for Windows.
- Experience with database management.
- Ability to create user-friendly interfaces and robust software functionalities.
- Prior experience in developing billing or financial software is a plus.

Please provide examples of your previous work and a timeline for project completion.