Edisto Island SC is one of my favorite beaches. The island has not been over-commercialized; no hotels, no scooter rentals. There is a grocery store, a few restaurants, and a few shops. There are beach houses you can rent but I'd rather camp!
The State Park has about 2 miles of beach, an "Interpretive Center" (nature center) and two campgrounds. One is right on the beach. I have never camped there. It fills up quickly and many sites are not shady, but it is nice nevertheless. The other campground is about a mile from the beach nestled in a live oak forest. I have camped there several times over the last 20 years. I was pleasantly surprised on this trip to find a big, new bath house. The campground was clean, calm and very pleasant. The rangers were friendly and helpful. The sites were adequate-to-large and almost all had some vegetation buffer between sites.