I want system in WPF/C# with following C# -Add/Edit/Delete Products -Add/Edit/Delete Customer -Add/Edit/Delete Barcode association with products -After Sell send print to three printers (Customer/DeliveryBoy/Cashier) -Manage Stock -Allow to enter cash on day start. Detail business will be provided to interested bidder. POS is common system so if you have already ready made system show me demo.