Online Mobile reservation and review services with maps (Like Uber, Agoda, Airbnb)

I want to develop a mobile app that can run on both Android and Apple. It is a services app where service providers can sign up and join in to promote their services. And potential clients can sign up and login to choose which services is best for them. Try and see how agoda and airbnb operates, something like that. There should be a database for both clients and sellers, and the app will get 20% commission for each deal closed. I cannot divulge the details of the service yet since I prefer a contract agreement for the winning developer to sign the non-disclosure agreement to ensure the code won't be re-sold to any potential competitor. There will be an integrated google map with all the potential sellers visually available. Client can choose the rates, services they want in the sorting menu. etc. Like what I said, think agoda.. or maybe Uber on this case since it is Mobile. On the owner's side. I want to have some decent level of control and view of the list of clients and sellers and their locations. Merchant account integration is also needed, they need to pay online. I am not a developer, so you will need to explain me the details on how this can be done. After the app completion, I will also need the source code and of course, I prefer it professionally made with details included so that the next developer will not have a hard time upgrading it in the near future. For the app, I also need the developer to work on minor changes when needed. But more importantly, bug fixes and patches at least within 6 months of it on live usage. The developer will also have to help me get this app up on the google market and iOS app download area.