Some dealerships do and some don't, you'd have to ask them.
Can you trade a car in at a motorcycle dealership?
If you can find one that will do it ! Some Harley dealerships will do it but they won't give you much of anything for the car as they'll have to wholesale it to get rid of it. You're much better off selling it on your own and using that money to put down on a motorcycle. Good luck finding one that will do that.
