That is why most travelers sell their car in the same state they bought the car in. Having said that, I can see the appeal of buying a car in Melbourne (Victoria) or Brisbane (Queensland) and selling the car in a state like Western Australia.t's nice to think that if you're buying your car in October with a May registration expiration that you're getting 7 months free registration. That's not altogether true. The seller will probably factor in the unused registration into the selling price of the car.