As you clear customs, go through the doors directly in front of you, about another 15 feet look to your left. You will be right in front of the Tropic check in desk. This isn't a large airport. I would say you would have no access to the duty free, as you are now in country. You can hit the duty free in the airport you leave the US from, as you have an international ticket. I have found that it saves a few bucks, but unless you really pour it down, it isn't worth the hassle of protecting those glass bottles in your carryon. I found the vodka on AC to be about $5 US higher for a bottle than at home. I haven't had any experience bringing beer INTO Belize, as I prefer Belikin to anything else we have available at home. Enjoy your trip and relax.