Build a Website

Currently my team and I are working on a start-up which involves an website and android app. We are looking for a good app developer who could help us develop an website/app with following features: 1. Olx type of website/App where the users communicate with each other using our platform. 2. Location identification by GPS along with map integration. 3. Location based limitation for the user, also option to use open type (without limitations) 4. Different categories of users 5. Different drop down lists to select 6. Developed software to be dynamic, easy to update /make changes if required. 7. Possibility to group people based on location and restrict the access only to people of that group. Possibility of having many such groups. Also this is a ground up website/app with great potential. So we would like to keep it agile and up to date. Prefer if could get everything on cloud with minimal physical server. Please let us know if you can find us a developer who can do this for us. Before we finalise the developer, we are looking for quotes from different developers to help us decide.