In my province, If a vehicle is damaged below a certain percentage of the new vehicle's value, a dealer can fix it without declaring the damage on the title.
I know of one example. A new Ford Explorer had front end damage (approx $3000) fixed and the vehicle was sold with no notes on the bill of sale. Because the value of the new vehicle was so high campared to the damage, the dealer did not have to declare it. It was not until the owner's friend, who owned a body shop, saw the damage, did the owner even know about it.
Although it would be the right thing to do, The dealer was not required to accept the vehicle back and didn't. They were stuck with it.