Jamaica is pretty expensive if you are trying to buy quality real estate.
http://www.realtor.com/international/search-listing/Tower-Isle_JM_CJM00012mjl/pg-2/
Costa Rica is a much better alternative.
Costa Rica is cheaper but it isnt as good as many make it out to seem. My friends mother is/was getting a house built there, a decent sized one, and there is all types of trouble with plumbing and sewage and other utilities. Said it was a nightmare. Im sure there may be better parts to build in than where she did (honestly couldnt tell u exactly where in CR), but shes already trying to abort mission and GTFO
DR's not bad either, but rent isnt all that great if you are just planning on moving there. Cost of living etc is cheaper than here so retiring is one thing but if youre just packin up shop and heading over there without a mint job lined up it probably wont end up being a good look, at least not for a while. One of my good buddies just got his own place there (hes born and raised DR) and he's going check to check essentially. He left his fam's house because they wanted him to give away his dog, then they were shocked he was like...nah imma just bounce and keep the dog.