I want to launch a straightforward, Czech-language marketplace app aimed at serious car buyers and sellers. The core idea is simple: every new advertisement costs a fixed 5 € listing fee, which should be handled seamlessly inside the app. Scope • Native availability on both iOS and Android so users can reach the widest local audience. • Phone-number verification as the sole sign-up and login method to keep profiles genuine and prevent spam. • Sellers need an intuitive flow to create a car listing, add photos, key specs, and pay the one-time 5 € fee. • Buyers browse, filter, and bookmark listings, then leave public user reviews once a transaction is complete. • A modest payment gateway (card, Apple Pay / Google Pay, or another solution you recommend) processes the listing fee and issues a PDF or email receipt automatically. Deliverables 1. Fully functional iOS and Android apps (store-ready builds + source code). 2. Simple admin panel where I can edit fees, moderate listings, and manage user-reported reviews. 3. Clean, Czech-language user interface; all copy provided by me, but the app must be translatable. 4. Documentation covering project setup, deployment, and basic maintenance. Acceptance criteria • A new user can register with Czech phone numbers, verify instantly, and publish a listing after successful payment. • Fees settle to my merchant account, and the ad appears in the catalog without manual intervention. • Buyers can rate a seller only once per completed deal. • App passes App Store / Google Play review and works on current OS versions. If you have experience building marketplace or classifieds apps, especially with lightweight payment flows, I’d love to see a short example of your past work and hear your proposed tech stack.