Georgetown should get you into the fringes of the Charleston market. The FM stations from Wilmington do well up along the southern Outer Banks of N. Carolina ,aka, The Crystal Coast, and hit Fort Bragg and Camp Lejeune and their surrounding towns well. The population really fluctuates in the greater Myrtle Beach area seasonally, but a bi-directional antenna on decent sized mast should provide good coverage due to the terrain. Good luck with the gig.