A Cat C could be like new once you've sorted it mate, nevermind a Cat D, that could be the most minor of work.
A lot of people will buy new cars that have had stuff re-done to them at the factory.
Say it had front bumper and wing damage and you straight replaced them, would it not be like new?
A good example is a guy we ensure at my work, he has a Bentley Continental GT, some bellend on a scooter went into the side of it and caused a right mess, no garage was willing to touch, technically by rights, that was a write off. Yet he spent 15k getting the panels put right by Bentley engineers, it would of been in better nick than before!