Review and Polish Rork App for App Store

I have a business app built with Rork, and a working version is already uploaded to TestFlight. Most of the app is complete, but I need an experienced developer to review the existing project, polish the user experience, fix bugs, and prepare the app for full release on the Apple App Store. The work should focus on improving the current codebase rather than rebuilding it from scratch. I also need help setting up and testing account login functionality and in-app payments or subscriptions. Please include your experience with Rork, Expo, or React Native projects, and provide an estimated price for reviewing the project, fixing and polishing the app, testing account logins, integrating and testing payments, testing overall functionality, and handling the full App Store submission.