The art of a good used car deal is one that’s been bought well – but it’s not as easy as it looks.

As baptisms of fire go, buying used cars is quite likely to lead to third degree burns, so I thought it was about time I jotted down the tricks and tips I’ve been given so far to help avoid buying a lemon.

For those of you catching up, I’ve been busy setting up my used car business – the Clever Car Collection – with the help of AI since the start of the year and now, nearly four months in, I have definitely learned the hard way that it’s not an easy business to master.

While AI has helped in a lot of ways, when it comes to checking over used cars I’ve been looking to buy, ChatGPT has not been particularly helpful. No, what this takes is experience (not something I’ve got) and a nose for a problem.

Over the last few months I have devised a process that has helped weed out (most of) the problem cars and I thought they were tips worth sharing in the video at the top of this page. 

For the car dealers reading this, I’d love to know what I’m missing, or the tricks you’ve used over the years. And for those consumers who stumble across this post, I hope the video and this article helps when you buy your next car.

Buying used cars is hard work… 

It didn’t take me long to realise the art of being a successful used car dealer is not in the selling – that bit is easy – it’s in the buying.

Picking up the wrong car for a bad price can lead to no end of problems. Even worse, buying a car with hidden issues can turn into a nightmare.

I soon learned you have to be on your guard. It pays to be suspicious of absolutely everything when you’re buying a used car. 

While there are many genuine reasons for selling, there are just as many good reasons to get rid of a problem car too – and it’s the latter I need to be careful of.

I’ve been to see cars with clutches on the way out, coolant in the oil, clogged exhausts and faulty injectors. Some I spotted, some I didn’t…

Now, I’m not a mechanic – by any means – but I follow a pretty simple process when I go to buy a used car for the Clever Car Collection that seems to work (most of the time).

Like I say, that doesn’t mean I haven’t been caught out. I have. But you learn from your mistakes, right?

Do your research…

I start with some homework. On the car buying websites I am getting stock from – the likes of Motorway and Carwow – there are a lot of details listed about the car’s previous history and I take my time to look through this in detail.

I play close attention to the MOT history. The government website lets you input a car’s registration and you can read back through all the past MOTs.

Here I keep an eye on advisories – these are the observations of previous MOT testers and while some are quite clearly ways of getting the previous owner to spend some more money with the garage, others give you a clue as to the condition of the car. Or issues.

They are especially helpful if the MOT has been carried out recently.

A few weeks ago, I checked the history of a Ford Kuga I was interested in buying and saw that three years ago the MOT tester had advised the rear subframe was corroded. A worry. 

It had also suggested a headlight had only ‘worked with a tap’. 

When I went to see the car I asked the owner if he’d fixed both items. Helpfully, he could then show me the bills for the underseal work he’d paid for and the new headlight. 

This owner was diligent. Others aren’t always this careful and without checking the MOT history I would never have known to ask. So take your time to read up on the cars you’re buying.

Look for lots of receipts…

When you get to see the car, spend as much time looking at the paperwork as the car.

I like to check the following:

– Make sure the V5C is in the owner’s name – and check it matches with some ID like a driver’s licence. It’s not rude to ask, it’s good practice.

– Check the VIN number on the car – often clearly visible under the windscreen – matches the number on the V5C. It’s the car’s identifying mark and as important that it matches as the car’s registration plate.

– Look at all of the servicing receipts and bills for the car. They can tell you far more than a service book. They detail exactly what has been done. And make sure you take them with you if you do buy the car.

– If the car is old enough to need one (and has one) check the owner has had the cambelt changed. And don’t just take a stamp in a service book as proof, demand a receipt, as it’s a pricey job (around £500). Google when it needs to be done on the car you’re buying, as each car is different, and remember it’s not always on mileage – it can be age too.

– Ideally, you want a stamped up service book. In the absence of receipts this is a good back up. But be suspicious if the same pen has been used and the same handwriting in subsequent years. I’ve seen service books where four or five years’ worth of stamps look like they’ve all been added at the same time. Some owners will stamp it up themselves to boost their car’s value…  so beware! It’s why I like to see the receipts.

Do some decent external checks…

I like to have a good look around the car before I drive it.

I’m looking for signs of crash damage. One white Nissan Juke I had planned to buy looked great in the pictures but when I saw it, the front and rear bumpers had been taken off a red car and poorly painted white. In the daylight they stood out like a sore thumb – and through the stone chips you could even see the red paint underneath! 

Look for panels that appear to be different colours. These could have been resprayed. They might have just have been fixing a scratch, or it could be something more serious.

Would I walk away from a car that had been repaired? Not necessarily. But I’d only want to buy the car if it had been done well.

I check every tyre for tread because they’re pricey to replace. I stick my finger in the tread and judge the depth. If it looks or feels low it probably is. Legally you must have 1.6mm across the width of the tyre but if it’s that low it needs changing. 

Make sure the car has two keys as well. I have no idea how people lose the spare, but they do, and on some cars they can cost more than £500 to replace. Ouch.

Other expensive things to fix are headlights, windscreens and wing mirrors.

What to look for inside?

When you get in, check everything works. And take your time to do it properly.

I’ve bought one car which I only later realised the fan wasn’t blowing any air out. That was an annoying problem to fix and required the dashboard to be taken out.

Try and connect your phone to the Bluetooth system too – I’ve had one car where that failed and hear it’s not uncommon to fail on others.

And make sure the sat nav works. Sometimes the cards containing the maps go missing and other times they just go wrong – so try it out.

Also check other extras that are important on the test drive: Does the cruise control work? Do all the electric windows go down properly? Do the mirrors move when you adjust them?

Under the bonnet

Like I mentioned, I am certainly no mechanic, but I still like to have a good poke around under the bonnet as there are often clues things might not be what they seem.

Anyone can check the oil – and if it’s too low, it’s a problem. Equally if it’s over the maximum that can be a problem too. 

Also check the coolant level. Cars shouldn’t lose coolant and if they do there’s an issue somewhere. If it’s not leaking under the car it could be getting into the engine and that is something to worry about.

I went to buy a car recently that a mechanic had written ‘ok’ and last year’s service date on the top of the coolant header tank. When I checked it was below minimum which made me very suspicious – enough, in fact, to walk away.

Why had the mechanic written it on there in the first place? Probably because it had been losing coolant before. It’s clues like this you need to keep an eye out for.

I look for cracks in hoses, broken wires and check inside the oil filler cap for any white residue. All signs it might not have been looked after very well.

Speak to the owner

I like to ask the owner why they are selling their car. You’ll work out pretty quickly if they’re telling the truth. 

I’ve had some owners fob me off with inconsistent answers in the past that don’t add up – like the multi-coloured white Nissan Juke – but it’s only by chatting that you’ll get a feel as to the sort of person they are.

Most of the people I have bought cars from are very genuine and selling for good reasons – moving abroad, needing a bigger car, just got a company car, etc.

But others I could tell were hiding faults and selling before the big bills crept up on them. I’d rather they had just been honest with me because I might still have bought the car if I knew what the fault was I needed to fix.

I chat to them while I’m checking it over. And on the test drive. Most people are genuine and honest – and you’ll get a feeling as to whether they are the sort of person who has looked after the car or not.

Sometimes you’ll get clues to problems while you chat too. Ask about recent services, repairs and if they’ve sorted problems you may have spotted on advisories on the MOT.

What to look for on the test drive

I write a list of all the things I want to check on each car before I go and see it and work through it methodically, because it’s easy to forget.

But while that’s easy as you’re walking around it, it can be hard to remember while you’re driving.

On the test drive there are a number of clues as to whether a car is working correctly.

The first one is obvious: Warning lights. If there’s one on the dash it has a problem. It could be minor and it could be major so I won’t buy it without knowing more. But you need to make sure your test drive is long enough for the lights to come on – I would suggest 15-20 miles and take in some motorway miles. 

If the service light is on, or there’s a warning on the dash it’s needed, then again that could be an issue – especially if it’s been ‘recently serviced’.

I listen for any knocks or unusual noises on the drive. A car shouldn’t make a knocking noise from suspension or wheels so if it does, it’ll need a repair of some sort. Again, it might be simple, or might not. 

I like to accelerate hard – especially in diesels – and check for any stuttering or smoke. Diesel Particulate Filters (DPF) can go wrong, so be wary of diesel cars that have done only a few miles around town as they won’t have had a chance to clear. They can cost upwards of £1k to fix.

Check for a wobbly steering wheel at motorway speeds – this could be dodgy tyres or wheels that need balancing. 

And, when it’s safe to do so, brake hard. Check for scraping noises, or crunching, as this could mean replacement discs or pads are required

I like to do lots of different speeds so make sure it’s not just a test route around town – getting it up to speed on faster roads is important as sometimes faults don’t show themselves until speeds increase.

Is the mileage correct?

This one worries me the most – so much so that I ask all sellers of cars to declare the mileage is correct to me in a written document.

I recently spoke to Trading Standards about this and they said it’s up to the dealer to do all reasonable checks that the mileage is correct – because it’s easy for previous owners to manipulate this.

I look at previous MOT records and make sure they match what I am seeing on the dash and I do a mileage check with an external company (HPI or Experian). 

It’s impossible to know completely if a car’s mileage is correct but by doing these sorts of checks you can cover yourself as best as possible.

What if the car is not right?

Sometimes the hardest thing to do is walk away from a car that doesn’t feel right – but I’ve done it on more than one occasion.

As a dealer, you have to stand by that car with a warranty and meet the consumer’s legal rights so I want to ensure the cars I buy and sell on are the best they can be. And that means being suspicious and checking things carefully and methodically.

One thing that has really helped is having access to an appraisal app. I’ve got this via my DealerKit DMS system and it lets me input any problems I spot and allocate a cost to fix them.

It also keeps a record of the checks so I can refer to them at a later date.

If I find problems it doesn’t always mean walking away though – but I will adjust what I can pay for that car accordingly. 

My best advice is be sceptical – remain curious about everything and ask questions. And if it doesn’t feel right don’t be afraid to walk away.

Even, if like me, you’ve taken a whole day out of the office to go and buy a car, it’s better to have wasted a few hours than it is to buy a dud.

But what am I missing? If you think there’s something else I can do when buying cars I’d love to hear from you. Message me via the email button below or find me on LinkedIn.

The AI Car Dealership Project Series

• Episode 1: I’m starting my own used car dealer with the help of AI
• Episode 2: I pitch my AI used car dealership idea to Mike Brewer
• Episode 3: Why do banks hate used car dealers so much? 
• Episode 4: We get a crash course in running a used car dealership…
• Episode 5: Here’s what I learned about buying used cars at auction
• Episode 6: Everything we’ve learned so far setting up an AI car dealer
• Episode 7: Can AI help me buy used cars?
• Episode 8: What I learned when I met a used car dealer professional
• Episode 9: Can a newbie buy used cars at auction?