Is it possible to combine activities in one port if one is not booking thru the ship? We want to do the cave tubing, thru xtreme, but would love to do some snorkeling afterwards. Is there easy access to snorkeling rentals? What about Roatan? Also is it possible to book the Dolphin experience directly? Or must we go thru the ship. According to the ships brochure, these are encounters, not swims.