The billing system -- 5

Hi, I am looking for a very professional developer to prepare the C sharp based billing system working on postgre SQL.

So far, I have a test data model and already developed UI and object - attributes addition functionality.

Remaining :
Production data model;
Calculation part;
Printing functionality.

If you are :
very proficient both with postgre sql and C #
Goal oriented
Passionate
Nice and trustworthy developer , you are welcome