The Spanish real estate market is incredibly opaque. Want to know how much your flat is worth? An agent will give you a number with no data behind it. A professional appraisal costs €300+. And listing portals show asking prices — not what properties actually sell for. What Quartio does: Type any address in Barcelona → get an instant price estimate Adjusted for your flat's specific features (size, floor, elevator, renovation, year built) See rental yield, comparable sales, mortgage simulation, and investment score Interactive price map of all 73 barrios with transport overlay Check if your property is in a rent-controlled zone (271 municipalities in Catalunya) Optional: AI-generated detailed report for €4.99 Where the data comes from (all legal, all public): Colegio de Registradores — real registered sale prices INE — Housing Price Index Gencat INCASÒL — rental prices from mandatory deposit registrations Catastro — property characteristics (surface, year built, floor) via free API Open Data BCN — neighbourhood boundaries, transport stops The tech (for the nerds): XGBoost ML model (R²=0.989) exported to pure TypeScript — runs in your browser, zero latency Point-in-polygon zone detection using real barri boundaries Next.js 16, Leaflet maps, 3 languages (ES/EN/CA), 271 static SEO pages No database — all data embedded at build time

Quartio

Enter an address and discover the value of your home

Enter an address and discover the value of your home