Buying a used car: what to check before you pay

Before you go to see the car

Ask the seller for the VIN, the 17-character chassis number. It is in the registration certificate (field E), at the bottom edge of the windscreen on the driver’s side and on a label in the door frame. A seller who will not share it is a reason for caution.

Enter the VIN and the advertised mileage in VIN Service Planner. You get the generation and engine, a list of what the service schedule required by that mileage, and the faults that appear on that engine around that mileage, with typical repair costs. If you do not have the VIN yet, pick the make and model.

What should have been done by that mileage

The most expensive maintenance items are not the yearly services but the ones that come round less often:

• Timing drive: a timing belt is replaced by mileage or by age, whichever comes first. A low-mileage car with an old belt has not been done.
• Oil in automatic and dual-clutch gearboxes: on many it is due at about 60,000 km, and it is often skipped.
• Brake fluid: every two years, whatever the mileage.
• Spark plugs, fuel filter, coolant and all-wheel-drive oil: the intervals are long, so the previous owner can easily leave them to the buyer.

Ask for invoices, not just a stamp in the service book. With no proof, assume the job has not been done and take that amount off the price.

Known faults of that exact model

Every engine and gearbox has its weak points and a mileage at which they usually show: timing chain, EGR valve, particulate filter, dual-mass flywheel, gearbox mechatronics. The model page shows which ones apply to the car you are looking at, at what mileage, and what the repair costs.

Ask the seller directly whether that fault has already been fixed and whether there is an invoice for it. An expensive repair that is already done counts in the car’s favour.

See the known faults of the model you are looking at:

Volkswagen Golf VII 2012–2020Škoda Octavia III 2013–2020Volkswagen Passat B8 2014–2023Opel Astra J 2009–2015Ford Focus III 2011–2018Renault Clio IV 2012–2019Peugeot 308 II 2013–2021Audi A4 (B8) 2007–2015BMW 3 Series (F30) 2012–2019Mercedes-Benz C-Class (W205) 2014–2021Toyota Yaris III 2011–2020Hyundai Tucson (TL) 2015–2020Kia Sportage (QL) 2015–2021Nissan Qashqai (J11) 2013–2021Dacia Duster I 2010–2017Tesla Model 3 2017–All models →

Mileage and history

• Compare the mileage with the service invoices and the roadworthiness test reports: each one records a reading, and the figures should rise steadily.
• Wear on the steering wheel, pedals, gear lever and driver’s seat should match the mileage.
• For an imported car, ask for the service history from the country it comes from. For cars from the United Kingdom, the MOT history with mileage readings is free on the UK government website.
• Paid vehicle history reports can show recorded damage and mileage readings from several countries. They are useful but not complete.

Recalls

An authorised dealer of the make can check by VIN whether the car has open recalls, and the manufacturer carries them out free of charge. The model pages list the published recalls, so you know what to ask about.

Inspection on the spot

Arrange for the engine to be cold when you arrive: a warm engine hides hard starting and chain noise.

• Cold start: the engine starts at once, with no rattle in the first seconds and no blue or white smoke.
• Warning lights: they all come on with the ignition and go out after the engine starts. A light that never comes on may have been disabled.
• Under the car and around the engine: no traces of oil or coolant.
• Oil and coolant: correct level and colour, no pale emulsion under the oil filler cap.
• Tyres: the same brand on each axle, even wear, age from the DOT code.
• Bodywork: differences in paint shade, uneven panel gaps, paint on rubber trims and seals.
• Interior: the air conditioning cools, all windows, locks, heaters and the screen work, and the car comes with a second key.

Test drive

Drive for at least twenty minutes, in town and on an open road.

• The clutch bites evenly and does not slip at full throttle in a high gear.
• An automatic gearbox shifts without jerks or delay, both cold and warm.
• The car does not pull to one side and the steering wheel does not shake under braking.
• The engine pulls evenly through the whole rev range and does not drop into limp mode.
• There is no knocking from the suspension over bumps.
• The engine reaches its working temperature and stays there.

Diagnostics and a workshop inspection

A cheap OBD reader shows stored fault codes, and you can enter a code in the app to get an explanation. If the codes were cleared just before you arrived, the reader shows that the system self-checks are not yet complete.

Before you pay, take the car to an independent workshop for an inspection on a lift. It costs little compared with the fault it can find.

Electric and hybrid cars

• Ask for a battery state-of-health (SOH) report from an authorised dealer.
• Check how long the battery warranty still runs. It is often about 8 years or 160,000 km, but it differs by model.
• Try charging on a normal (AC) and a rapid (DC) charger: a failed on-board charger is an expensive repair.
• Check that recalls and software updates have been done.

How to negotiate the price

Add up what is due but not done and what is coming in the next year. The app gives a typical price for each item, so you can show the seller a concrete list rather than an impression.

A car with a tidy history and the big items done is worth more than a cheaper one that still has all of that ahead.

The checklist is a guide and does not replace an inspection by a qualified workshop. Prices and intervals in the app are indicative.