Most people spend more time checking their phone than they do checking a car they're about to spend thousands on. Don't be that person. A thorough viewing takes 45–60 minutes and will either confirm the car is worth buying or save you from an expensive mistake. Both outcomes are valuable.
This walkthrough covers everything — from the moment you arrive to the moment you drive away (or decide not to). Work through it systematically, not all at once in a rush.
Before You Even Get Out of Your Car
Park opposite the car and look at it from a distance before approaching. Does it sit level on all four corners? A car that leans to one side may have suspension, chassis, or frame issues. Are the panels all the same shade, or can you see variations in the light? Painters rarely match metallic paint perfectly — even small colour differences suggest a panel has been resprayed after repair.
If the seller has the car running when you arrive — particularly on a cold morning — be slightly suspicious. They may have warmed it up to hide a cold-start rattle or a difficult-starting engine. Ask them to turn it off so you can start it cold yourself.
The Exterior Check
Walk slowly around the entire car in good daylight. This is not optional — viewing at night or in the rain is how sellers hide the things you need to see. The torch on your phone is genuinely useful here.
Panel gaps tell you whether the car has had accident damage. Run your fingers slowly along the door edges, the bonnet gap, and the boot lid. The gap should be even and consistent all the way along — on a well-assembled car it barely changes. Uneven gaps, particularly a bonnet that doesn't sit flush or a door that has a narrower gap at the top than the bottom, suggest a panel has been removed, refitted, or replaced after impact. A car that's been repaired correctly after an accident isn't necessarily a bad buy — but knowing about it before you make an offer gives you accurate information to price with.
Paint variations are the other side of the accident story. Shine your phone torch along the bodywork at a very low angle — almost parallel to the surface. Factory paint has a uniform, consistent depth and texture. Repaired areas show up as ripples, slightly different surface textures, or small runs and drips in the finish that weren't there when the car left the paint shop. Under the low-angle torch, the difference between factory paint and a repair is usually visible even when the colour match is excellent.
Rust on a UK car of any age is worth checking carefully. Look at the sills — the strips between the front and rear wheels under the doors — the inner and outer wheel arches, and underneath the rear of the boot floor. Shine the torch inside the front and rear wheel arches specifically. Surface rust on otherwise intact metal is cosmetic and doesn't affect structural integrity. Bubbling through the paint, flaking metal, and holes in the metal are structural rust that affects the car's safety, its MOT eligibility, and its repairability. Structural rust on the sills or chassis is a reason to walk away.
Check the windscreen carefully for chips and cracks. A chip in the driver's primary forward field of vision can fail an MOT and, more importantly, can spread into a full crack as temperature changes stress the glass. A stone chip is typically £30—£70 to repair by a mobile resin service and takes thirty minutes. A crack requires windscreen replacement at £200—£600 depending on the car and whether the screen has embedded rain sensors or heating elements.
Tyre condition deserves slow, close attention on all four wheels. The legal minimum tread depth is 1.6mm across the central three-quarters of the tyre, but wet-weather safety drops significantly below 3mm. Check the tread depth with a 20p coin — if the outer rim of the coin disappears when inserted in the main groove, you have at least 3mm. Look at the wear pattern: even wear across the full tyre width is normal. Wear on the inner or outer shoulder indicates incorrect wheel alignment or worn suspension components. Wear concentrated in the centre indicates the tyre has been consistently overinflated. Any of these patterns tells you something specific about how the car has been maintained.
Check all the lights: headlights on full beam and dipped, rear lights, both front and rear indicators, reverse lights (engage reverse gear with the engine running), and brake lights. Ask the seller to stand behind the car while you press the brake pedal. Cracked or moisture-filled light clusters fail MOTs. Checking the lights takes five minutes and is a common skip that produces a surprise at the next MOT.
The Interior Check
The first thing to do when you open the door is use your nose before your eyes. A damp smell — musty, faintly mouldy — means water is getting in somewhere: a door seal that's perished, a sunroof drain that's blocked, a boot seal that's failed. Left untreated, water ingress produces electrical gremlins, corrodes connectors, and eventually creates mould that no amount of cleaning fully removes. Cigarette smoke penetrates headliner, carpet, and seat foam in a way that air fresheners mask rather than eliminate. Either smell should factor into your negotiating position.
Check the wear on the seats, carpets, and pedal rubbers against the claimed mileage. A genuine 40,000-mile car should have seats that look barely used. A 90,000-mile car will show visible wear on the driver's seat bolster and some fading at the carpet edges — this is normal and expected. What catches mileage fraud is the rubber on the foot pedals, specifically the brake pedal. These wear down on every single journey and cannot be restored. If the pedal rubber is worn through or has chunks missing on a car claiming 40,000 miles, the mileage has been adjusted. Cross-reference it against the free MOT history, which records the mileage at every test going back years.
Test every button in the car. This sounds tedious, and it is, but it costs you nothing now and potentially hundreds of pounds later if you discover a fault after purchase. Test the air conditioning — not just the blower fan, but the compressor actually engaging. You should feel the car's idle drop very slightly as the AC compressor kicks in. Test heated seats on both sides, electric windows on all four doors, mirrors, sunroof, Bluetooth pairing, and the infotainment screen through its main menus. Minor electrical faults are cheap to overlook at the viewing stage and expensive to trace once you own the car.
Turn the ignition to position two — one click before the engine starts — and watch the dashboard warning lights illuminate. They should all go out once the engine starts. Any warning light that stays on after startup needs a clear explanation before you proceed. An engine management light covers a vast range of faults from a loose fuel cap to a failing catalytic converter. An ABS warning light means the ABS system may not function in an emergency stop. A transmission warning light on an automatic car can mean expensive gearbox work. None of these lights should be dismissed on the seller's word that “it's been like that for a while and it's fine.”
The airbag warning light deserves a specific mention because it's sometimes treated as minor. If the airbag warning light stays on after startup, the airbag system may not deploy correctly in a collision. This is not a cost calculation — it's a safety issue. A non-functioning airbag system is not something to fix later. Either get a confirmed diagnosis and repair receipt before you buy, or walk away.
Under the Bonnet
You don't need to be a mechanic to check under the bonnet — you're looking for obvious signs of neglect or serious problems, not performing a full diagnostic. Start with the oil. Pull the dipstick out, wipe it clean on a tissue, push it all the way back in, and pull it out again for a clean reading. The level should sit between the minimum and maximum marks. More telling than the level is the colour and texture: black oil that smells faintly burnt is simply old and overdue a change — common on a used car and not concerning by itself. Milky, creamy, or frothy oil is a completely different matter. It means coolant is mixing with the engine oil, which almost always indicates a blown head gasket. This is a repair that runs £800–£2,000 or more depending on the engine, and it's non-negotiable — if you see milky oil, close the bonnet and leave.
Check the coolant reservoir, which is a translucent plastic tank usually near the front of the engine bay. The coolant level should sit between the marked minimum and maximum lines. Most coolant is green, blue, or orange depending on the type used. Brown, rust-coloured, or oily-looking coolant indicates either serious neglect — the coolant hasn't been changed in years and has degraded — or oil mixing into the cooling system, which leads back to the head gasket concern. The colour of the coolant is a simple, immediate read on how well the engine has been maintained at a basic level.
Ask the seller whether the car has a cambelt or a timing chain, and if it has a cambelt, when it was last changed. Many modern engines use a timing chain, which is a metal component designed to last the life of the engine and doesn't need scheduled replacement. But engines fitted with a rubber belt — which includes most petrol engines built before the mid-2010s and many diesels — must have that belt replaced at the manufacturer's specified interval, typically every 60,000–100,000 miles or every five to seven years. A belt that hasn't been changed on schedule is a ticking failure. On interference engines (the majority), when the belt snaps, it sends valves and pistons into each other and destroys the engine. If the service history doesn't confirm a recent belt change on a car with high mileage, factor a full belt service (£250–£600 depending on the car) into your offer — or don't buy it.
Finally, look for leaks. Check underneath the car for any fresh oil or coolant on the ground where it's been parked. Look around the engine bay for wet staining on hose connections, around the valve cover gasket at the top of the engine, and around the sump at the bottom. A small patch of dried, ancient oil around the sump drain plug is extremely common and inconsequential. Fresh, wet oil seeping from a gasket or around a hose junction is an active problem. Coolant leaves a white mineral residue when it evaporates — look for this around hose ends and at the top of the radiator.
The Test Drive
Ask to drive it yourself — not just as a passenger. The seller should expect this. Drive for at least 20–30 minutes, including some faster roads if at all possible. Many problems are invisible in a slow car-park circuit and obvious at speed.
Start the car cold. If the seller pre-warmed it, ask them to turn it off and give it 20 minutes before you restart it. Cold starts reveal things a warmed engine hides: timing chain rattle is most pronounced before the oil circulates fully, difficult starting shows up only from cold, and cold-idle hunting (the engine revs fluctuating at idle before it's warm) can indicate throttle body or idle control issues. Once the engine is running, sit for 30 seconds with the radio off and listen at idle — a rhythmic knocking suggests bearing wear, a bubbling sound from the cooling system is a head gasket warning, and a persistent hiss often means a boost or vacuum hose has a split.
At some point during the drive, accelerate hard — enough to reach motorway speed from 30mph. The engine should pull cleanly and progressively through the rev range without hesitation, stuttering, or a flat spot. Check the mirrors during and after a hard pull for smoke from the exhaust. Blue or grey smoke means the engine is burning oil; white smoke on a warm day that doesn't clear in a few seconds suggests coolant burning. Either is a reason to investigate before proceeding.
Find a clear stretch of road and brake firmly from about 50mph with no traffic close behind. The car should slow in a straight line — if it pulls to one side, that indicates either a seized caliper or significantly uneven brake pressure between the wheels. Any vibration through the brake pedal under firm braking suggests warped discs, which typically cost £150–£300 per axle to fix. A grinding noise means the pads are worn to metal. None of these problems are catastrophic on their own, but all need pricing into any offer you make.
On a manual car, pay attention to the clutch biting point. With the handbrake on, press the clutch to the floor, engage first gear, and release the clutch very slowly. The point at which the car begins to pull against the handbrake is the biting point. On a healthy clutch, this happens in the middle third of the pedal's travel. If the car only bites near the very top of the pedal — almost fully released — the clutch friction material is nearly worn out and replacement is not far away. A full clutch replacement typically runs £400–£700 depending on the car, so it's a meaningful negotiating point.
On a straight, flat section of road, briefly take your hands off the steering wheel at a steady 40–50mph. The car should either track straight or drift only very gently in one direction. A car that pulls firmly to one side indicates misaligned wheels, uneven tyre pressure, or uneven tyre wear. Alignment can be corrected cheaply; if it's caused by worn suspension components, the cost rises significantly. Also turn the steering wheel from full lock to full lock at very low speed and listen for any clunking or clicking from the front wheels — this is the sound of worn CV joints, which are a standard wear item but add a repair cost to your purchase.
When you return from the drive, let the engine idle and walk behind the car. Blue/grey smoke from the exhaust means oil burning. White steam is normal condensation on a cold day; persistent white smoke when the engine is warm means coolant burning — head gasket concern.
The Paperwork Check
Sit down with the V5C logbook and check the registered keeper's name against the person you're dealing with. The name should match and the address on the logbook should match where you're viewing the car. If you're buying from a private seller who is “selling it for a friend” and their name doesn't appear anywhere on the logbook, you have no legal certainty that this person has the right to sell the car. The VIN — the 17-digit vehicle identification number — on the logbook should match the VIN plate you can see at the base of the windscreen on the driver's side, and also the number stamped in the doorjamb or chassis plate. Any mismatch between these is a serious concern and warrants a HPI check before going any further.
Work through the service history carefully. Genuine service history is stamps in the book supported by invoice printouts, or digital records from a main dealer or independent garage. Stamps that are smudged or difficult to read, garage names that don't show up when you search online, and books with stamps but no supporting invoices are all red flags. Self-stamped service books — where the seller has bought a rubber stamp and stamped the book themselves — exist and are entirely worthless. If the history looks inconsistent or the garages listed don't appear to be real businesses, treat the car as having no service history and price accordingly.
Cross-reference the mileage on old MOT certificates against the service book entries and the current odometer reading. The mileage should increase consistently year by year. A car that recorded 47,000 miles at its 2022 MOT and now shows 82,000 miles has covered 35,000 miles in four years — plausible for a regular commuter. A car that recorded 74,000 miles three years ago and now shows 61,000 miles has a clocked odometer. The free MOT history check — available through GOV.UK or through AllCarsUK — shows every recorded mileage at every annual test going back a decade. Check it before you go to view, and use it again now if anything you see at the car raises questions about the mileage consistency.
Check the MOT history before you go →
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Also see: How to Buy a Used Car | How to Negotiate on Price | Avoid Used Car Scams | Outstanding Finance Guide