Looking for a Full-Stack Flutter & Node.js Developer for "NearByt" (Local Marketplace MVP)

I’m looking to hire a skilled full-stack developer to build and launch an MVP for NearByt—a free-first, hyper-local marketplace platform focused on proximity search and zero-commission person-to-person trading. The Core Value Proposition: Unlike traditional classifieds that charge users or restrict communication, NearByt promises free listing, free chat, free calls, and zero transaction commissions for everyday users, monetizing instead via local business profiles and targeted advertising. Tech Stack Required: Mobile Frontend: Flutter (Cross-platform Android & iOS) Backend API: Node.js (NestJS preferred) Database & Proximity: PostgreSQL with PostGIS (for distance radius queries like 1.4 km away) Real-Time Communication: WebSockets (Socket.io) for unthrottled chat MVP Scope (Sprint Breakdown): Auth & Profile: Firebase OTP phone login with verification status badges. Discovery & Feed: Geolocation feed with distance range filters (1km, 5km, 10km, etc.). Listing Flow: A fast, multi-step form to upload photos, title, price, and auto-tag location in under 60 seconds. Communication Hub: Real-time chat rooms tied to listing IDs, plus direct calling and "Make an Offer" triggers. Admin Moderation: Basic dashboard to review listings, manage reports, and handle user bans. Next Steps: If you have experience building scalable mobile marketplaces, handling geospatial queries in PostgreSQL, and building smooth Flutter UIs, please share: Examples of 2–3 production mobile apps you’ve built (specifically listing or chat apps). Your standard availability (hours/week) and estimated timeline/budget for an MVP scope like this. Looking forward to your response!