totally depends on price and what you want. My car is a Cat D. Mechanically sound, but the bumpers had a cheap spray and the paint is coming off, some of the plastic trim under the cars is broken and the wings,bonnet,bumper don't line up exactly. Do I care? not at all as I got the car for under 50% of what a normal version would go for.
i almost bought a cat c 180sx a long time. the car was made in 96 (i think) and it was declared cat c 10 years later when it was worth nothing. the write off value of a 10 year old nissas is nothing, hence that cat c was a perfectly servicable car.
but unless you understand how it works, dont touch them tbh