Charleston is great but not a lot of great places to stay there. I second the vote for Kiawah. Perhaps my favorite resort, ever. Once, staying there, a palm tree blew over outside our condo and I noticed it going into Charleston. When I got back, late in the afternoon, the tree was gone, the hole filled in and the grass in place. You had no idea it was even ever there. It is a bit laid back with great golf, tennis and biking. A handful of great places to eat and a few more just outside the gates. Then, of course, you can go into the city.
Bohikits Marina is a good place to eat (or charter a fishing boat) or Gilligans (for cheaper food). If you want a lot of night life, go someplace else. The place has five of the best golf courses on the east coast all designed by different people (Fazio, Jones, Nicklaus, Player). And, of course,
the famous Ryder Cup course with seven (IIRC) holes on the ocean.
Also, in the north, is a similar place named Wild Dunes. If you really want to get away, go to Bald Head Island off of Wilmington NC but that isn't Charleston, of course.
You can go through a local realtor, VRBO or AirBnB. Personally, I like the windswept condos on the ocean or, if you want to save a few bucks, the Night Heron Park or Inlet Cove condos. You rent a bike for the week and the entire island has paved bike trails. Also, they do have a couple of hotels if you want daily maid service. One is named the
Sanctuary.
My "move" was to golf, tennis, beach, bike, fish or pool all day. Hit the showers at 3ish, and drive into Charleston (or so) for an awesome dinner. its about a 35 minute drive, if memory serves. Then, I'd be in bed by 10 to get up at 6:30 in the am to do it again (tee time, or just a good cup of coffee before the fam got up).