Our neighbors received a letter today explaining they owed their car taxes, since they had paid their car tax when requested, they went into the tax office with receipt to prove paid. They were told that yes, they had paid their car tax, but there is a second car tax that needed to be paid? Is there 2 different car tax payments that need to be made each year? Can anyone tell us what the difference is between the two payments, what is each one for? Being new here, we haven't had to pay yet, so we need to know ourselves for October when ours is due. Unfortunately our neighbors Portuguese is limited, and the tax office employee had limited English.