I am using destinationweddings.com and once I had my block of rooms from the hotel set aside, I urged all guests to get the group room rate that will be less expensive then booking later on. I told them that I couldn't guarantee how many rooms beyond the original 20 I could get and they would be smart to book one of them now. It worked and we booked all 20 rooms within 3 weeks. Any room that didnt get booked in the first 4 weeks my FI and I would have to pay the deposit of 100 for each room. I didn't want to have to do that if I didn't have to. Oh, Elizabeth "Cookie" Randall is my WC/TA there and she's awesome!