Sullivan’s Island SC beachfront Homes For Sale | Homes For Sale on the Ocean Sullivan’s Island SC. Properties for sale on Sullivan’s Island beach with water views. Sullivans Island real estate is some of most expensive in the U.S. not to mention residents don’t move very often so prices usually hold strong as supply is fairly low on a regular basis. Sullivan’s Island real estate is some of the most coveted property in the United States, not only SC. With such a small island houses don’t come up for sale very often especially in a good market.