When I would inspect vehicles as an adjuster I always contemplated buying one that I had totaled from Copart or the owner. I had access to the owner, new the facts of loss, had experience finding damage, and knew people that would do body repairs on the side. I STILL didn’t take that chance. We totaled cars that were repairable all the time that would’ve been solid candidates. Reasons would be: length of repair time, a single part being on national backorder, owner far away from home when a wreck occurred, fear of a giant supplement, high salvage value on the damaged vehicle, etc.
Understand you may be throwing away your money if there’s some major issue you don’t see or can’t possibly be aware of. But…the majority of them were running and driving at some point and are likely repairable with the right amount of work. Also, as GON said, I’d stick to cars being sold by insurance companies exclusively.