There's probably nothing wrong with the car, in fact if it's had any welding done and been done properly, it's possible that it's stronger than other focus'.

Personally, I wouldn't touch a CAT D car because of the same reason you posted on here and you can guarantee other people have been hesitating over buying this car.

When you come to sell it, it will take alot longer unless it's stupid cheap compared to others of same spec.

Sassy and Guzzlers old 3 dr is the prime example, it was stunning but took quite a long time to sell.