Private island ownership in Costa Rica is unique and restricted by the Maritime Zone Law. Foreigners cannot buy islands in territorial waters; instead... Read More, they acquire a 20-year renewable concession (lease). Non-residents are limited to a 49% stake in these concessions unless they have five years of residency, often necessitating a corporate partnership. The first 50 meters from the high-tide line is public, meaning no island can have a truly "private" beach legally closed to the public. Read Less