What to Do If a Car Check Finds a Problem
Don’t pay yet. Some markers end the deal outright, some change the price, and some are innocent with a paper trail — and the seller’s reaction to being asked is often more informative than the marker itself. Here’s each flag in turn, what it means, and the rule for deciding whether to negotiate or walk.
Finance marker
A live finance agreement means a lender owns the car. It’s not a reason to walk by itself — a lot of cars are sold with finance outstanding — but it’s a reason to change how you pay. The seller gets a settlement figure from the lender; the finance is either settled before the sale, with the letter to prove it, or you pay the lender directly and the seller the balance. Then you re-run the check before you drive off. A seller who wants your money first and promises to settle afterwards is asking you to trust them with the one thing the check exists to prevent. The full sequence is in our finance guide.
Write-off marker (Cat S or Cat N)
A write-off category means an insurer once decided the car wasn’t economic to repair. Category S is structural damage repaired; Category N is non-structural. Both can be back on the road legally, and both can be perfectly good cars if the repair was done properly. Both are also worth materially less than an equivalent unrecorded car, and harder to insure and sell on. Our categories guide sets out exactly what each letter means.
What to do: if the seller didn’t mention it, that’s your answer — they either didn’t know, which means they didn’t check, or they did and hoped you wouldn’t. If they did mention it, ask for the repair invoices and photographs, get an independent inspection, and price the car as a Cat S or N, not as a clean one. Categories A and B are scrap-only and shouldn’t be on the road at all.
Stolen marker
Walk, and report it. There’s no negotiating position on a stolen car — it isn’t the seller’s to sell and the police will seize it from you. Don’t confront the seller; note the details and report through 101.
Mileage discrepancy
A reading that goes backwards in the MOT history is either a tester’s typo or a clocked car. A typo is one reading out of sequence, corrected at the next test; a step down that stays down is not. If it’s clearly a typo, the seller can ask the DVSA to correct it and you can proceed. If it isn’t, the car’s real mileage is unknown and it should be priced as a high-mileage car with a full service due — or, for most buyers, left alone.
Plate or colour changes
Mostly innocent. Private plates get bought and sold; a plate change or two is normal. Several in a short period, or a plate change that coincides with a keeper change, deserves a question. A colour change is rarer and always worth asking about: a full respray is expensive, and people do it either because they love the car or because something needed covering. Ask which, and look at the panel gaps and the paint in the door shuts for the answer.
Negotiate or walk: the rule
Walk on anything that goes to ownership: stolen, leased, a seller who isn’t the person on the V5C, a VIN that doesn’t match. Negotiate on anything that goes to value: a Cat S or N with a documented repair, a plate history that checks out, high mileage that’s honest. Treat a mileage discrepancy as ownership-class unless the typo explanation is obvious. And in every case, watch how the seller responds to the question. Someone who has nothing to hide shows you the paperwork. Someone who gets defensive has already told you what you need to know. Run the check before the deposit, not after.
Car check problems FAQs
The seller says the finance marker is a mistake — what now? Ask them to get written confirmation from the lender that the agreement is closed. Genuine mistakes get resolved in a phone call; the seller who won’t make it has made your decision.
Can I insure a Cat S or Cat N car? Yes, though some insurers decline or load the premium, and you must declare it. Undeclared write-off history can void a policy.
My report shows a plate change — is that bad? Usually not. Private plates transfer between cars all the time. Multiple changes in a short window are worth a question.
Should I tell the seller what the check found? If you’re negotiating, yes — it’s the basis of your offer. If you’re walking away from a stolen or fraudulently described car, no. Just leave and report it.
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