Interesting topic, I live in MA and have to pay sales tax 5% when you register a vehicle and exise tax yearly, NH on the other hand does not have sales tax so people who own property in both states often register thier cars, boats, or whatever to thier NH address. Check this out, call 1800IPAYTAXES and listen to the message. It is a hotline setup to catch these people. Do you think they would set this up if it was not a problem, they were not serious about catching people doing it, and they were not making they pay for thier indescresion? MA and NH are small states, if they are doing this here you can be sure they are doing it in CA and other areas.