We want to do some modification to SambaPOS

We are looking for someone to develop and customize SambaPOS open source POS system. You will need some understanding of SambaPOS v3 and need excellent skills in C# .NET 4, XAML and SQL Server. We need the following features to be added. I have attached screenshots of features we want to add. When making changes to the code please try to keep the current style of code. Full stock controls Promotions management Customer managment and extensive configurable customer loyalty programs Employee management, deliveries, Email receipts, physical receipts and A4 Invoice options Superfast transaction processing Data backup Business intelligence reporting with alerts and real-time reports OFFLINE AND ONLINE(locally connected to many pc.)