where do you live in CR? my old girlfriend was down there a few months ago birdwatching. eco tourism has fallen off the edge of the world, they almost did not get the guide because there were only 4 people and he usually had 5 minimum. but she loved it.
what do you use to pump water and refrigeration? do you go native for cooking or preserving food? that is the biggest need for power, imo. anybody can live without heat and AC, in temperate climate, but you gotta have water. can you get propane or is it more expensive than gas or diesel? anyway, a generator could pump water to a storage cistern, chill the fridge, and provide some power each day if you used a small generator for a few hours each day maybe 4 hours total in 4 shifts, and then you can store power in batteries for lighting overnight, and be off the grid, without the windmill. you may not have enuff sun for solar if it is cloudy a lot, but that is where solar could help, and solar for hot water is super effective too.