This is a bit theoretical question, maybe viable for a wiki.
Suppose you want to buy a 10yo car and among available deals you see one with suspiciously low mileage (e.g. 5'000 km). Seller assures you that the car was bought for his parents and spent 95% time in garage, ideal condition exterior, but no service brochure.
What are the clues that could indicate the real car mileage if it was spoofed?
I'll make this a wiki answer so others can add to it...
The first and most obvious thing is the old saying "if it looks too good to be true, it probably is".
Look at the condition of the interior, particularly the driver's seat and steering wheel. Does the pattern of wear match what you'd expect for the stated mileage?
Paperwork - do they have anything to back up their claims? In the UK, the mileage is recorded at each year's MOT (roadworthyness) test, so that's usually a good reference. Again, if they've 'lost' the paperwork, be suspicious (in recent years they have computerised the MOT system, so you can look up the last few tests for a car)
Personally, I'd avoid a very low milage car just as I'd avoid a very high milage one. Cars don't generally like sitting around for long periods unused - rubber parts perish, things sieze and stick, etc. Go for a decent, honest, average-miles car that looks like it has been looked after.
Pull off the air cleaner ductwork and look at the throttle body plate. If it has a black carbon buildup on it, you can be sure it's been driven much more than 5000km.
For more scientific results, try sending an oil sample to a company like Blackstone Labs. They'll look at the wear characteristics and amounts of trace materials in the oil, and can often tell how much use it's seen based upon which materials are in the oil.
It's possible that they'll be able to verify their low-mileage claim through a service like Carfax as well, but many dealerships and service shops choose not to submit information to Carfax.
I tend to agree with Nick C though. Engines fare much better when they're used regularly. An engine that sits for long periods doesn't circulate oil to all the internal components of the engine, and as the oil settles back into the oil pan, components can begin to rust. As a general rule of thumb, an engine that hasn't been driven in a month is at risk of breaking down. I would lean toward a well-maintained, well-documented, regularly-driven vehicle instead of a 'too good to be true' low-mileage vehicle.
Yes you can make out the changes and confirm whether the odometer was rolled back by the following procedures:
Were the tires ever changed? Does it have original equipment brand/model/size tires? Are the tires bald or overly worn?
Do the tires look ten years old? Tires should only really last about 5 years and driving on them at ten years old is probably very dangerous. If you end up purchasing the vehicle and you think they are the original tires, change them.
Check for holes drilled in the bodywork where taxis tend to mount their permit plates ...
A friend of mine bought a citroen bx and was really happy he had a low miles car.
Until he showed us that is and we saw the holes and suggested his 60k miles car was more likely 260k miles : it did not last long , clutch , suspension, rattled like stones in a bucket.
Moral, check everything....
As per the comment, this was in the UK, but those magnetic vinyls are also used now... So also look at wear patterns on gear knob, steering wheel even plastic finishes "polish" ...
You can visit such websites as EpicVin, VinInspect, VinGurus and VinChain to identify the real mileage.
