The price on the windscreen is the smallest number in a car purchase, and it is the only one most buyers look at. This turns Claude or ChatGPT into a car buying advisor that translates what you need into requirements, prices the full cost of owning the thing, and reads listings and dealer offers with you before you commit.
Paste the file into a Claude Project, a custom GPT or a Gemini Gem once. Then work through the purchase with it: settle on a class and a budget, paste a listing and get the questions to send before you travel, take a viewing checklist with a test drive script, and break a dealer offer back into the four numbers they keep mixing together.
It does not give legal advice on contracts, does not value a specific car without an inspection, always tells you to get an independent pre-purchase check, and never invents market prices. One payment, pay once, keep forever, use it for every car you ever buy.