1 The full service history — not just whether it exists
Most buyers ask "does it have a service history?" and stop there. The more important question is whether that history is complete, consistent, and makes sense for the car.
Look at the intervals between services. A car that was serviced religiously until three years ago and then nothing since is a red flag. Check who did the work — a mix of main dealer and independent specialists is completely normal, but big gaps or unrecognised stamps are worth questioning.
For higher mileage cars, timing belt or chain replacement records matter a lot. If the manufacturer recommends replacement at 60,000 miles and the car is at 75,000 with no record of it being done, factor that cost into your offer or walk away.
A full service history from a single main dealer adds value. A patchy history doesn't necessarily mean a bad car, but it should always affect the price you're prepared to pay.
2 A proper HPI or vehicle history check
This is non-negotiable for any used car purchase. A vehicle history check tells you whether the car has outstanding finance on it, has been written off, reported stolen, or has a mileage discrepancy recorded anywhere in its history.
Outstanding finance is the big one. If someone sells you a car that still has finance owed on it, the finance company can legally take the vehicle back from you — even though you paid for it in good faith. This happens more often than most people realise.
A check costs around £10-20 and takes five minutes. There is no good reason not to do it.
If a private seller is reluctant for you to run a history check, that reluctance is itself a reason to walk away.
3 The condition of things that are expensive to fix
Cosmetic issues are easy to spot and easy to price in. What catches buyers out are the things that look fine but aren't — and carry big repair bills.
A few specific things to check:
- Tyre condition and age. Tyres degrade with age as well as mileage. Check the date codes on the sidewall. Tyres over 6 years old should be replaced regardless of tread depth.
- Brake disc condition. Grooved or heavily worn discs aren't always visible but are expensive. A brief test drive will often reveal a pulsating pedal or pulling under braking.
- Any signs of oil or coolant leaks. Look under the car and check the oil filler cap for a creamy residue, which can indicate a head gasket problem.
- All four windows, all electrics, all lights. Test everything. Fault lights on the dashboard should be investigated, not accepted at face value.
On a used car, a pre-purchase inspection by an independent mechanic is well worth the £100-150 it typically costs. Not every seller will allow it, but most legitimate private sellers and dealers will.
4 Whether the price is actually fair
Most buyers spend time looking at whether a price seems reasonable relative to other listings for the same model. That's a decent start but it's not the full picture.
Prices vary significantly based on spec, mileage, location, condition, and how long a car has been listed. A car that's been sitting on AutoTrader for three months at the same price tells you something. A car that appeared yesterday at a competitive price tells you something different.
Check what the same model with similar mileage actually sold for recently, not just what sellers are asking. Glass's Guide and CAP valuations are used by the trade — some consumer tools give you access to these now too.
And don't be afraid to negotiate. Almost every used car has room in the price. A polite, factual offer based on condition and market comparables is completely normal and generally well received.
5 What you're actually buying in terms of ownership costs
The purchase price is only part of the cost of owning a car. Before you commit, it's worth spending 10 minutes on the running costs for the specific model.
- Insurance group. The same car in a higher trim level can sit in a significantly higher insurance group. Check before you buy, not after.
- Road tax rate. Older diesel cars are now significantly more expensive to tax in many cases. Check the VED band for the specific car.
- Service costs. Some manufacturers have very reasonable fixed-price servicing. Others are eye-watering. Look up what a routine service actually costs for that model at an independent specialist.
- Known issues. Every model has its quirks. Spend 15 minutes on the relevant owners forum and you'll quickly learn what tends to go wrong and how much it costs when it does.
A car that costs £2,000 less to buy but £600 more per year to run and insure isn't necessarily the better deal over three years of ownership.
The honest summary
Buying a used car well takes time, knowledge, and a willingness to walk away from something that doesn't check out. Most buyers have the willingness but not always the time or the knowledge.
That's exactly the gap a car sourcing agency fills. We run through all of this on your behalf, on every car, every time — so you don't have to.