It may not be reasonably priced, but consider spending the night near Charleston.
Coming from Alabama, DH and I got an opportunity to head out a day early, and spent the night in Savannah, GA. We had a romantic dinner, and stayed in a wonderful hotel in the historic district. We took the Trolley tour of Savannah the next day. It is a beautiful city!!!
If interested, we stayed at the Hampton Inn on MLK, Jr. Blvd. for $95. We didn't know what kind of bargain that was for that hotel.
I'm guessing Charleston and Savannah are similar in some ways.
We are much more into the history, architecture, antiques, etc. than golf, fishing, and beaches than Hilton Head offers, so our side trips to Savannah made our Hilton Head trip much more enjoyable to us.
(We ended up with a combo trip of great history and architecture mixed with the marsh, the beach, and the dolphins!)