Modify Existing shopify app

I have an affiliate app that enables a single store to have affiliates sell the product with a link. We can call this the "master store". Currently, affiliates would not have their own store to sell, they would just utilize a link to sell from the master store. The master store chooses the price of the products, not the affiliates. The affiliate app keeps track of what affiliates sell so the master store can pay them a percentage. I need to modify the app to be able to connect to an affiliate stores that they can create themselves, so they can choose their own pricing on their own store, but have the orders get send back to the main store for processing after purchase. We would need to make it so that the payment of the item gets a percentage split to multiple parties, not just the affiliate store. I need this done ASAP.