I saw this question after answering your other question. Now I know that you want to sell one home and buy another. First and foremost, sell your home before buying another.
Is your credit score impacted by any late payments on your existing home? If so, that will complicate getting a mortgage on the new home somewhat, but still workable.
Identifying why your score is what it is, can also help understand what your best options are. Locate a trusted buyer's agent in Charleston, SC and explain your situation to them. They should have lenders that they work with on a regular basis who can help out. You can also checkout the web reference to this email for sources of good exclusive buyer agents in the Charleston area.