A used car is one of the largest things most people buy without professional help. The good news is that the checks that protect you are cheap or free, and most take minutes. This guide runs both sides of the deal: what to check before you buy, and how to sell without losing money or getting scammed.
Buying: research the model before you look at cars
Before you look at a single advert, decide whether the model is worth owning at all. Every car has known weak points, and the ones that turn up at MOT are the ones that cost you.
Learn what fails on the model
Our reliability pages show how a model holds up as it ages, built from every MOT test on record, so you know what tends to fail and what a garage is likely to flag. If you are still choosing between options, the rankings compare models against each other on the same measures. Go in knowing the pattern, and a seller cannot talk you past it.
Set a realistic budget
Budget for more than the sticker price. A used car needs tyres, servicing, and the odd repair, and the cheaper the buy, the sooner some of that lands. Leaving a maintenance buffer is not pessimism: it is what stops a bargain turning into a money pit.
Check the exact car before you view it
The advert describes the car the seller wants you to see. A few free checks describe the car that actually exists. Do these before you spend an evening driving to look at it.
MOT history: failures, advisories and the mileage record
A free MOT history check is the single most useful thing you can run on a used car. It shows every past failure, every advisory the tester noted, and the mileage logged at each test. The same data sits on the government's check MOT history service; we draw the chart and flag the anomalies so the pattern is obvious at a glance. A car with the same advisory ignored year after year is telling you something.
Mileage and clocking
Wound-back odometers are still common, because every 10,000 miles knocked off adds to the asking price. A mileage check reads the sequence of recorded readings and flags any point where the number falls or jumps implausibly. A clean, rising line is reassuring. A dip is a reason to walk, or at least to ask hard questions before anything else.
Clean-air zones
If you drive in or near a charging zone, check it before you buy, not after. Our ULEZ checker shows whether a car is compliant, so a cheap older car does not turn into a daily charge that dwarfs the saving.
What public data cannot show
Be clear about the limits of free checks, because this is where buyers get caught. Public data is excellent on how a car has been maintained. It is silent on three things that can cost you the whole car.
We cannot see any of these: they live on private industry databases, not the public record. A paid HPI-style history check does read them, and on a private sale it is worth the small fee for peace of mind. If a car is still on finance, the finance company can legally repossess it even after you have paid the seller.
Where the paid check earns its place
If the free checks look clean and you are serious about the car, a paid history check is the honest next step. It is the one thing that closes the gap between what we can show you and the risks that would leave you out of pocket with no car to show for it.
The viewing and test drive
Data narrows the field. The viewing is where you confirm the car in front of you matches it. View in daylight, in the dry, and never in a hurry.
Cold start and the mechanicals
Ask the seller to leave the engine cold for your arrival: a warm engine can hide a hard start or smoke. Watch the dashboard as it starts, and note any warning light that stays on. On the drive, listen for knocks and whines, feel for a slipping clutch or a gearbox that baulks, and check the brakes pull up straight.
Bodywork and accident repair
Look along the panels in good light for uneven gaps, a colour that does not quite match, or overspray on rubber seals: all signs of accident repair. Uneven tyre wear can point to tracking or suspension damage. None of this is automatically a dealbreaker, but it should match what the seller has told you, and it is leverage on price.
Paperwork on the day
Check the service history is real, with stamps or invoices, not just a promise. Most of all, confirm the V5C logbook is present and that the registered keeper's name and address match the person selling to you, at the address you are standing in. A seller who is not the registered keeper, or who wants to meet somewhere neutral, is a reason to pause.
Haggling and knowing when to walk
You have done the work. Now use it. Every flag you found is a fair, specific reason to pay less, and your willingness to leave is your strongest card.
Use the flags as leverage
Tie your offer to what you found: a recurring MOT advisory, tyres near the limit, a service that is overdue. Concrete points are far harder to argue with than a round-number lowball, and they show the seller you know the car.
Be willing to walk away
There is always another car. If the story does not add up, the paperwork is wrong, or the seller will not let you check, walk. The Citizens Advice guide to buying a car covers your rights and the warning signs in more detail.
Selling: prep, presentation and price
Selling well is mostly about removing reasons for a buyer to knock money off. That starts before the car is even advertised.
Get it ready
Clean it properly, inside and out: a valet costs little and pays for itself in the first offer. Fix the cheap niggles that make a car feel neglected, like a blown bulb or a wiper that smears. Gather the service history, the MOT certificates and any receipts into one folder. A car with a paper trail sells faster and for more.
Price it to sell
Research what the same model, year and mileage is actually selling for, then price against reality, not hope. An overpriced car sits, goes stale, and ends up selling for less than a sensible price would have got on day one. Price to sell, not to dream.
Where to sell, and the trade-offs
There is no single best route, only a trade-off between how much you get and how much hassle you take on. Pick the one that fits your time and patience.
Rough ranking, not a rule. A tidy, in-demand car does better privately; a tired or awkward-to-sell car may be worth offloading fast. The gap between private and trade prices is the fee you pay for convenience.
Match the route to the car
A clean, popular model with history is worth the effort of a private sale. If you value a clean break, or the car is hard to shift, taking a little less through part-exchange or an instant buyer can be the right call.
Paperwork and staying safe when you sell
The sale is not done when you shake hands. A few steps protect you from being liable for a car you no longer own, and from being paid with money that never arrives.
Tell DVLA the day it goes
The moment the car changes hands, tell DVLA you have sold it. This ends your liability for tax and any charges, and triggers a refund of any full months of tax left. Give the buyer the green "new keeper" slip and keep a record of their name and address. Do not hand over the whole logbook.
Getting paid safely
Wait for cleared funds before the car leaves. A pending transfer, a screenshot, or a cheque is not cleared money: it can be reversed or bounce after the car is gone. Be wary of buyers who overpay "by mistake" and ask for the difference back, or who want to pay a deposit without seeing the car. Meet at your address, in daylight.
Handing over and cancelling
Once you have been paid and the buyer has the green slip, cancel your insurance for the car and stop any direct debit for tax. Remove your details from any connected apps or trackers. Keep proof of the sale, including the date, the buyer's details and the confirmation from DVLA, in case a fine or query lands later.
Selling a car that is still on finance
If there is finance outstanding on the car, you cannot simply sell it. On hire purchase and PCP the lender legally owns the car until the last payment, so the car is not yours to sell yet.
Settle it first
Ask the lender for a settlement figure, pay it off, and only then sell the car free and clear. Selling a financed car without settling first is an offence, and it leaves the buyer exposed to repossession. Our guide to PCP, HP and cash explains settlement figures and voluntary termination if you are not sure where your deal stands.
Common questions
What paperwork changes hands when I buy or sell?
The V5C logbook. When you sell, you give the buyer the green "new keeper" slip (section V5C/2) and either tell DVLA online or post the rest of the logbook. Keep a note of the new keeper's name and address. You should also get the service book, MOT certificates, receipts for work done, and both keys. Never hand over the full V5C: it is proof of the registered keeper, not proof of ownership.
How do I pay, or get paid, safely?
For low value, cash is fine but count it in a safe place. For most cars a same-day bank transfer is cleaner: as a seller, wait until the money actually shows as cleared in your account before the car leaves, not just a screenshot or a pending notification. Be wary of overpayment scams, part-payment "holding deposits" from buyers you have not met, and anyone rushing you. Meet at your home address, not a car park.
What are my rights if the car turns out faulty?
It depends who you bought from. From a dealer or trader the Consumer Rights Act 2015 applies: the car must be of satisfactory quality, fit for purpose and as described, and you have a short window to reject it for a refund if a fault shows up. From a private seller you have almost no protection: the only real requirement is that the car is "as described", so a false claim can be challenged but general wear and hidden faults are your risk. This is why viewing carefully matters more on a private sale.
What does a paid history check show that free data does not?
A paid HPI-style check reads private industry databases we cannot see: outstanding finance still owed on the car, insurance write-off records (Cat S or Cat N structural or non-structural damage), a stolen marker on the police database, plate and colour changes, and mileage entries from sources beyond the MOT. Free public data covers MOT history, tax and recall status. The paid check earns its place on exactly the risks public data is blind to.