Build a Joomla module

Develop a joomla 2.5 module. There are 2 kind of users (groups): managers and vendors. Vendor is able to view: - form to add new contracts (fields: code, name, description, date, price, expiration date) - view a list of all contracts added by himself ( in a modal or lightbox ) Manager: - form to add new vendors (standard fields: username, password, name, surname, email) - view a list of vendors added by himself - view a list of all contracts added by his related vendors No need a template, just the module with these basic functions.