I have 21 rooms each on two charachters - which is to say, 1 of every room ever sold or offered on a game or card - One is my main charachter which is a "total" charachter, meaning it has one of everything (except some beta stuff and a stinking Sparrow costume) and the second charachter has 4 of everything which is currently for sale or offered on a card.
My main storage charachter though has 250 Skull Rock rooms, my goal there is to fill each room with one item (IE: 1 room for Skeleton at the Helm, 1 room for Yellow Carpet chairs, etc) - there are, currently, 252 furniture items which have been available in the game, approximately 158 of them are still for sale, so I really only need about 158 of the rooms.