I don't know about the sailing schools on the East coast but one of the sailing schools down in Kemah, TX offers an option to sleep on one of the boats they have available for charter in the marina whilst taking the ASA 101/103/105 courses. The prices are supposed to be quite cheap and there are some hotels close by if you felt you needed to get off the boat. I don't think you would be sharing with anyone either. It might be worth asking any sailing schools you were looking at about this type of option.
As for ASA 104 one of the requirements is that you spend a night on the boat, so you wouldn't be able to avoid that.