Dont want you to rethink your trip, I live on Caye Caulker because I love it, but have been to alot of the places you mentioned, lived in Hawaii for 26 years. After this trip you may want to check out the Bay Islands of Honduras, they are awesome , beautiful sandy beaches, volcanic mountains, snorkling from the beach and less expensive. You will also love Caye Caulker its got a very unique personality. To answer your questions the water taxi will take you round trip to the mainland or San Pedro for $15 R,T, Most of the cave tubing is in the Cayo District.

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