Last time I did it, I got copies of the paperwork from the seller (as I hadn’t fully paid for it yet) I then submitted that and a bill of sale to u.s. customs to be able to export it out of the states. I think they wanted 3 days to do their checks on it. They would then approve you able to do that. Then, I paid and picked up the car and came to the Canadian border. (Sumas on a weekend) and they checked the paperwork and had me pay GST (not sure if I paid pst too) The biggest hassle was getting a rookie at the counter who didn’t want to allow the u-haul trailer into Canada with Arizona plates!! Finally someone came up and explained to him that it was ok.