[DotNetDevelopment] AutoVAT System - A web application

[Anchit]

Hey,
Can you people please guide me in developing a web-based application
for AutoVAT system that lets a corporate take care of its taxation
filings? What can be the possible modules to make in the project, and
I will be grateful if you can also provide me the possible Use Case
Diagram and DFD.
Thanks,
Anchit.