Bird cups with hooks on them work quite well for water in the carriers. There is a nested set of two in green or purple that PetSmart sells in the bird dish area. The smaller one just fits on the door next to a white cup for food. Those semi-round cups can be purchased in a pack of two in a bag called a travel pack, which also has an absorbent pad and "Live Animals" labels for the carrier. I have seen those at PetSmart hanging from clips on the shelving at the back of the store. Our humane society also sells them in their store. The ferrets will dump the cups so they must be fastened to the door with something. The 2" mini-clamps from Home Depot, etc. work well but must be put on the inside of the door on the top of the cups so the cups stay level. If put on from the outside they tilt the cup upward. In the small carrier I have seen a triangle litter pan attached to a rear corner by a 1/4" bolt. Take the carrier apart, drill a couple holes and fasten it in there, put in some pelleted litter, and put the top back on. Then hang a small hammock and put a receiving blanket on the floor and you are ready to take that trip to the vet's. The medium size carrier with straight sides such as Kennel Cab 2 is my favorite as a small cat litter pan fits across the rear of the cage; it just has more space for the food and water cups. The pan is also bolted in, with 3/8 inch bolt. The ferrets can be in there all day at the vet's or on a long trip. Carol J.Owens Ferret Friends, Inc. Tucson AZ [Posted in FML 6512]