I built a 100% local invoice reader with Ollama + n8n — the real trick was teaching it NOT to guess

I'm not a professional developer — I run a small business and I'm self-taught (HTML/CSS/JS, a bit of Python). Every month I had the same chore: a pile of PDF invoices and me copying supplier, date, concept and total into a spreadsheet by hand. Boring, and full of typos.

I automated it with n8n, but with two hard rules:

Invoices never leave my computer. They're supplier and business data — I didn't want to push them to any cloud API.

No monthly subscription per model call.

So I ran it on Ollama locally (qwen2.5-coder:7b) instead of a paid API. It works on a normal laptop — a Ryzen 7, 16 GB RAM, no pro GPU — at ~12 s per invoice and €0 cost per run.