The flea markets just outside the gates are just a...

The flea markets just outside the gates are just as safe as inside with police officers and licensed travel agents. They can only have the cruise terminal with so many things and agents. Trust your gut and verify your agents credentials, support the locals outside the gate and help their economy locally without the 3rd party taking a cut of the profit.
Shop local, buy from the makers, the mom and pops. We had a tour of the island and then shopped the flea market by our terminal. Also family of our driver. They also take credit, and the prices are amazing!!!! Remember cash though cause the local banks can not offer cash advance without your passport and your bank needs to set that up months before travel. Our tour guide was accommodating for our lack of cash and only credit. Outside the gates is primarily cash.