Some people allow them free roam of their house, or certain rooms of their house. However, we recomend that you have a cage to keep them in when you are not home to supervise. The larger the cage the better, particularly the more ferrets you have. In the cage some popular items are hammocks, sleep sacks, towels, shirts, other material for sleeping, and litter boxes. You should have a carrier of some sort for trips to the vet, or out to the park, etc.
More litter boxes for around the house.
A corn cob, or wood pellet litter is preferred by many. Ferrets need to be entertained, so a variety of toys should be provided. Kong toys are popular and durable, and most ferrets love sacks, boxes, and such items. You can make tunnels for them out of dryer hose, Oatmeal containers, soda boxes, and tape. Newspaper or carpet scraps are useful.