RMH POS Integration with Valor Terminal

I need a skilled .NET developer to integrate RMH POS (Retail Management Hero) with a Valor Android payment terminal. This integration requires real-time data sync.

Key Integration Features:
- Transaction processing
- Refund processing
- Sales reporting

Authentication Method:
- API key

Ideal Skills and Experience:
- Proficiency in .NET development
- Experience with RMH POS and Valor payment systems
- Strong understanding of real-time data synchronization
- Familiarity with API key authentication

Please provide examples of previous similar work and ensure you can meet the project's requirements within budget.