Category D write off?

[finkykun]

Im buying a car, it has been classed as a category D write off, it is only 3 years old and has all relevent paperwork etc, I know that category D in the minor bracket as long as it is repaired to good standard?
Some cars if they are less then years years old are supplied new? is this so and what do people think i should do? should i be wary>?

Category C and Category D Registered Cars