I have brought two in from Washington, one on a trailer and the other on its bottom. Have a title search done, get two bills of sale from the vendor, one for the boat and one for the trailer. Make sure the value is clearly written on the bill of sale. You will get charged HST at the border. Before you leave Washington, contact the Registrar of Imported Vehicles (in Victoria I think). They will issue you a permit to operate the trailer in BC and there is a small fee for this. As with any imported vehicle, you will need to get the trailer inspected before it can be licensed. Canadian Tire is an authorized inspection facility. Contact a Government of Canada service centre for an application to register the boat. Mail it back east, get the number and registration certificate and you are good to go. It really is a surprisingly painless process. Depending on the width of the boat, Washington State may require wide load signs and a flashing amber light. Check on that when you pick up the boat.