It takes a while to sink in.

A few hours pass, and it still feels surreal, as if you're merely house-sitting, borrowing someone else's wealthy lifestyle, waiting for her to return and relieve you of your time in paradise.

But after a day or so, the fantasy becomes reality: You're on an island all your own, the days and nights and sand and sea are all yours, and there's no one to feel beholden to - not even the family of pelicans guarding the wooden dock in the turquoise water.

This is life on Sandy Cay, one of two unbelievably affordable private islands for rent off the coast of Utila, itself a tiny island about 30 kilometres from mainland Honduras. And though "affordable" is relative, it's hard to argue with a two-bedroom, two-bathroom house shrouded from civilization by a thicket of palm trees, perched on a patch of white sand out in the Caribbean Sea for $US100 ($A98) a night.