Adamal wrote:2. The car was sold, but the registration was not sold with the car, meaning that the plate seller isn't legally entitled to sell the plates, no matter what they think.
You can't separate registration from the car. The plates belong to the car, therefore the owner of the car (registration being a non-tangible belonging).
You can separate the plates (rego number) from the car, but the registration is still tied to the car. If the rego number was changed, then they would have recieved new plates to affix to the car.
Take the plates but don't attach to a car for a year until the heat has died down in my opinion. Orignal seller will have no idea where they've gone.