"I guess that since insurance write-off status will follow a car around forever, in there is a clue that there are some things no specialist can detect? Is this the simple answer?"

It would need to be measured very precisely in all dimensions and stripped back to where the damage "was".

For some people, buying one as a keeper if the price is right "might" be a reasonable idea,

BUT, in the MotorTrade, there are plenty people economical with the truth. of Bad as some, (not all) Franchised dealers are, I don't think you would see a Cat N or S car on the forecourt and I don't think any of the supermarket chains would have them as well.

Tells me everything I need to know.

Do you want to risk your life and that of your loved ones,

Myself no.

I guess that since insurance write-off status will follow a car around forever, in there is a clue that there are some things no specialist can detect? Is this the simple answer?

I think it reflects mainly the fact that most buyers won't consider a damaged/repaired car because they aren't easy to sell or re-sell. My own car was repaired 3 years ago as an insurance write-off, having been driven away from the collision. At 12 years old it has little intrinsic value, but as it is 100% reliable (so far) I have not tried to dispose of it, but if I did, I would expect to get few takers.

The tricky ones may be cars damaged early in life while they are still 'valuable' enough not to be written off. At least older ones like mine are 'honest'.

Edited by Andrew-T on 23/09/2020 at 17:44

Some of this depends on the age/value of the car at the time. A new expensive car could have more serious damage , but still be economically repairable. An old banger might only need some superficial damage to be written off.