Here's what I have found with help from a friend in TN that goes to Anegada.

CLT-STT using AA to STT and Island Birds to get Anegada RT cost is $4,200
CLT-SJU-EIS using AA to SJU, Cape Air to EIS and Island Birds to Anegada RT cost is $2,950
CLT-MIA-EIS using AA to MIA and codeshare to EIS then Island Birds to Anegada RT cost is $3,200

I have not used Fly BVI yet. I asked them for a quote from SJU, STT and EIS. We'll see what they respond with.