Unless you can find a commercial fuel dock, you're probably going to be
charged road tax anyway. In addition, you're paying a premium for
convenience and also more to cover the massive liability insurance they
fuel dock is forced to carry. In many states, you can get a rebate of
the road tax as long as you show you're putting the fuel into a boat.
This is fairly significant.. save your receipts! You can see the policy
for your state he http://www.fhwa.dot.gov/ohim/hwytaxes/2001/pt5.htm