Motor vehicle sales tax rates differ greatly while in the United Tells. Car tax by state often varies within counties and urban centers. If you are moving to another state, calculating car tax prior to moving possibly be useful in determining when and where to own. However, if you are trying to stop the car tax from your home address, go ahead and buy a new home to park your car in because unless you possess a house or have a home in the state in question you risk tax evasion. Car dealers and lo...