Job description
We need to build a billing management (database) and payments processing system that is comprised of 3 main parts or modules, as described in detail in the attached flow-chart image.
The goal of this system is to be able to bill customers AGNOSTIC/INDEPENDENT of initial payment processor (such as Stripe.com) used, and to be able to collect order data from 1 website and bill from another.
With a centralized admin panel to manage everything.
It must support major payments processors and be easy to add APIs of new/custom payments processors.
You are free to use an existing billing system that's already built as the core.
Once this initial build is complete and fully functional, we will need many further features and expansions so consider this a job with future possibilities.