Two of us are planning to visit Belize from 12/18 thru 12/25. Do we need to make reservations for lodging...or can we find a cheap place to stay in Caye Caulker and around San Ignacious when we get there?

We will be leaving on the early afternoon on the 25th. Will we have a hard time getting a bus from San ignacious area or water taxi from Caye Caulker