A2billing Reseller Customization

Would like to offer calling card services through a reseller website who is not in my line of business. Whenever a customer registers for his service , i'd like to generate an account for his(reseller) customer in a2billing. The solution should also be able to top up the account dynamically from reseller/agent account balances in a2billing. i should be able to deploy the solution to multiple [login to view URL] the solution can generate a2biiling accounts for all Reseller's old customers,that will be great