Just as there is no perfect cat, there is no perfect cattery. Most breeders must work within the confines of available space, number, sex, and breeds of cats to be housed.
Financial considerations are always a factor.
There are, however, a few general things to think about. If possible, have the cattery on the ground floor. Hauling litter up and down stairs should be avoided. Have the cattery easily accessible and keep no more cats than you can comfortably take care of. Above all, keep the design simple .