We're renting one on Isle of Palms, SC (by Charleston, SC) in July. There are lots to choose from there and the other islands close by (Sullivan's,Folly Beach, etc.) We rented a 3 BR 1300 ft house that shares a pool and beach access with 4-5 other houses that are exactly the same size and circle the pool. They have much larger ones available if you don't care to split up.
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www.vrbo.com