Simple Invoice System using JAVA and MySQL

I need a JAVA programmer to create an simple invoice system that will contain the following:

Use MYSQL as a database

A client database. Be able to know how much a client has purchased up to date.
A product database
A invoice database. Keep invoice history.

Those 3 dababases or tables (depending on how you program it) should interact together.

Ability to print invoices
Ability to create backups.

I will request the source files. This is basically all the important parts of this simple invoice system. How much would you guys charge me to create this system?

Any offers?