Build Vtiger Module

Hi. I need to customize vtigerCRM modules. The first project is the following: I need a subscription module added: - Fields to include: Company name (LOOK UP FIELD) Subscription Plan (LOOK UP FIELD) Next Billing Date (DATE FIELD) Subscription Status (DROP DOWN FIELD) - Need a subscription tab under the organization profile also linking to this module. - Would like a workflow also to create a service contract in the service contract module that is based on the plan selected. For example a Gold plan would have a agreement created with unlimited support via phone, chat, and portal. However the basic will only allow for portal support with no agreement. Please view vtiger information on development BEFORE bidding. I would appreciate it.