I think the actual legal tax rate is 10%, but I'm not exactly sure. Regardless, get a quote that INCLUDES taxes and any insurance that you want to purchase and compare them straight up at the final, total price, and go from there. It appears to me that SOME car rental companies play with the numbers, perhaps adding TOT, which they are not supposed to do, and/or some other items, to boost their bottom line. Car rentals are a very tough business to be in, in SXM. So, again, get your total price and see if you can live with the total price, regardless of how they say they arrive at it, compare total price versus total price and make your choice. If they quote you 18% tax, you might try and say that tax should only be 10% and see what they say. To me, I just ask them to give me a price, including tax, and go from there.