So basically you didnt tell to the dealer who traded-in that your car has been heavily wrecked, simply because it has not been reported and visible on a carfax report, right ?

If this is the case, I think the community will appreciate your honesty...

BTW, I would say always do an inspection of a used car instead of telling people to always buy new. Some crooks exist, but a proper inspection should prevent most of bad surprises.