I didn't spot it being a cat d first time round, my mistake. Actually, I don't see it as a problem as long as there's evidence of the original damage. My other car was written off 3 years ago but it got repaired and I still use it. I was aware that Lexus only replace the belt, but it's still a good price. If you include the water pump etc some main dealers will do it for around £500. I was quoted that by an independent.
The Gumtree car is still a good buy I think, if it passes a good going over that is.