For a project like that, trust comes from structure, not premises.
Make sure you (not the developer) own the Google Cloud/Maps account, payment gateway, domain, and app store accounts. Use a simple contract with a clear scope, and pay by milestones (demo first, then maps, then payments, then admin, then final testing). Also ask for the code to be in a repo you can access from day one.
Cost depends on your location and how advanced you want it, but a basic MVP (customer + driver app + admin + maps + payments) is usually $5k-$30k+, adn adding KYC and more features can push it $20k-$80k+.
Are you starting with Android only or both iOS and Android? That alone changes the quote a lot.
This should be taken consideration. Especially the owning of domains, hosting, payment gateway apis, and every api the app uses, also the difference of using test and production apis. Although this kind of app is not so unique since there are several ride hailing apps so cost will not be so high.
Payment integration sometimes have different cost depends on the company it uses. Some payment gateways ask initial payments, then add fix or percentage per transaction. So you should take it into consideration.
But total cost in my area it would be like $3k - $5k. As for KYC, idk about the cost of companies related to compliance, i will not add the cost of this. Unless, you or your team manually doing it, approving every KYC application.
