There are four levels of damage used by the insurance industry to describe cars that have been involved in accidents. These levels, or categories as they're more commonly known, are labelled as A, B, C and D.
Cat A cars
This type of car is the worst of the four. Vehicles in Cat A cannot even be used for salvage and should be crushed.
Cat B cars
These vehicles still have serious damage but they may be broken down for spare parts.
Cat C cars
These vehicles can be fixed, but the repairs alone will cost more than the car's market value, so it has been written off.
Cat D cars
As with Cat C vehicles, Cat D cars can be fixed - but the repairs will cost less than its market value. However, the insurance company's decision to repair the vehicle is dependent on more than the cost of the repairs.
A Category D write-off can often be caused by moderate damage. The insurance company also has to take into account the cost of a courtesy car and inspection fees once the repairs have been completed. So it might decide that it doesn't make financial sense to repair the Cat D car.
If that's the case, the insurer can decide to sell the car to an independent garage, which then repairs the car for less money and is able to sell it on to the public.
Let's say you find one of these Cat D cars in the classifieds. Is it worth looking at or should you move on right away?
If you've done your homework, know what to look out for and what questions you need to ask, you can pick up a real bargain.
Here are our six top tips for buying a Cat D write-off:
Buy the car from a dealer instead of a private seller
If you buy a Cat D car from a dealer then you have more consumer rights. A car dealer has to declare everything they know about a car; a private seller only has to make sure the car is as described.
Ask lots of questions
What damage did the car sustain? Where were the works carried out? What parts were replaced? The insurer doesn't have to release any information about how the car became a write-off, but some well-targeted questions to the dealer can help you uncover what happened.
Get an inspection
This will cost you upwards of £200 - a major investment when you're attracted to the car because of its low price - but is well worth it. An inspector knows what to check and could find accident damage that was missed. The AA, RAC, Dekra and Autolign all offer inspection services and could save you from buying a car that's potentially unsafe.
Pay for a history check
What if the accident isn't the only thing you need to think about? Just as with a conventional secondhand car, a history check will show up if the vehicle has been stolen or is subject to any outstanding finance.
Be wary of newer cars offering really big savings
The old adage, 'If it looks too good to be true, it probably is' definitely applies here. A really low price on a newer car could be a sign that the repair work has been done to a budget and isn't of satisfactory quality.
Avoid cars that could have chassis damage
Bodywork damage can be relatively easy to fix - but chassis damage will continue to cause headaches even if a repair has been attempted. You should be doubly careful if you discover the car has had a problem in this area.
If you think a Cat D car is worth the gamble and you've decided to buy one, there are two further things to consider:
Tell your insurance company
Make sure you inform your insurance company that the car's a Cat D. It's likely that it'll have to be marked on your policy; otherwise you risk having any claim turned down in the future.
Investigate a warranty
Some used warranty suppliers will provide cover for Cat D cars. It could be a surprisingly cost-effective way of giving yourself some peace of mind about your new purchase and any repairs that have been made.
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