I’m building an Android app that lets private commercial owners handle their annual tax in one place. The user journey is straightforward: 1. A driver opens the app, creates a personal profile, and adds one or more vehicles with key fields such as registration number, owner’s name, seating capacity, and any other basics we agree on. They can update these vehicle records at any time—right up until they press “Send Tax Request.” After that point, the data must be locked to guarantee consistency for both the payment gateway and the admin workflow. 2. When a user is ready, they generate a tax request from the stored vehicle card. The request is pushed to an admin dashboard where I can see every submission, change its status, and trigger responses or reminders. 3. The final checkout step routes the user to an in-app payment screen. I haven’t settled on a gateway yet, so please leave room for PayPal, Stripe, or Square; I’ll confirm which one during development. The API keys and callback handling should be cleanly abstracted so we can swap providers later if needed. 4. As soon as payment clears, the request status needs to update automatically in the admin panel and reflect in the user’s history screen. 5. admin can upload a pdf file to the request sent as receipt completing the request. 6. admin would have multiple user on his side to manage/assign request. Core deliverables • Android client (Kotlin or Java) with profile management, vehicle CRUD (restricted edit), tax-request flow, and payment integration • Simple, secure admin web panel (framework of your choice) that lists, filters, and changes request states • RESTful backend or Firebase setup to sync data between app and admin panel • Documentation for build, deployment, and environment variables Acceptance criteria • Users cannot edit vehicle data after submitting a tax request • Successful payment returns an unmistakable success state in both app and admin panel • Admin actions instantly propagate to users via standard Android notifications or in-app refresh If you’re comfortable with Android architecture components, secure payment SDKs, and a lightweight admin interface, this should be a smooth build.