How an Interior Designer Built a Construction SaaS Using AI in 50 Days — Without Writing a Single Line of Code

From renovation sites to React deployments — a story of building software with Claude and ChatGPT My name is Kostiantyn. I've spent 20+ years in construction and interior design. I run a design studio, manage renovation projects, calculate estimates. And every single time a new project started, I opened the same spreadsheet, copied columns, fixed formulas, made mistakes, recalculated. One day I did the math: creating one estimate from scratch takes me 3-4 hours. Finding current material prices — another hour. Calculating how many bags of plaster I need — calculator, notebook, manufacturer's website, comparisons. Every project — starting from zero. I'm not a programmer. Never took an IT course. Don't know React, don't know SQL, never heard of Supabase. But I had something else — 20 years of understanding exactly what a person standing on a construction site with a tape measure actually needs. So I built a SaaS platform using AI. The Market That "Doesn't Exist" Construction estimates in