Each contract can choose product from the existing products in the library;
Each contract can record the total amount of the project and the times of payment and the amount of each payment;
Each contract can record the real payment amout;
This system uses a large amount of Ajax and jQuery and other advanced technology to ensure the stability of the system.
System after many rounds of testing to assurance quiaty( interface testing, functional testing, security testing, concurrent testing, stress testing)