$17 for residents, $27 for nonresidents according to the DCR website. They also rent yurts out but that price is not listed. They mention that there is an electric power station nearby and that you may notice a low frequency noise. Check in time is from 1-9. Quiet time from 10-7.
Yes, there is tent site right behind the entrance but I am not sure about prices.
Thanks! Your answer is awaiting moderation.