I am somewhat confused by this paragraph? My understanding was that any boat sold by a dealer in Canada was subject to Canadian tax. My understanding was that Canadian boats sold by individuals and delivered to the US, there was no Canadian taxes due. Someone please correct me if I am wrong.
On the US side, the state taxes would be paid wherever the boat was registered. THE ONE THING YOU HAVE TO DO IS GO TO THE INTERNET SITE OF THE INDIVIDUAL STATES AND SEE WHAT THEIR SPECIFIC REQUIREMENTS ARE!
Some states require you to register a boat in that state if it is used in the state for a specific period of time. Used may, or may not, be defined as actually usage and in the water ready to be used.
As noted previously, some states (or counties within the state) also have personal property taxes. Don't know if that applies in NY or Vermont, but worth checking on.
Jim