All those aggressive, territorial tendencies are the work of hormones. So, if you want a ferret, get it fixed when young, before any bad habits have had time to form. This does not hurt the animal mentally or physically and the alternative is a sly little carnivore that will sneak up on you at the most inconvenient moments and sink 1-inch canines into your ankle. As relatives of the skunk, ferrets have scent glands that should be removed. The odor may be pleasing to other ferrets, but most people find it objectionable.
Ferrets also require different medical prevention from dogs or cats.
They are much more susceptible to distemper, which will almost always lead to their untimely demise. They need vaccinations early in life, at about three weeks of age. They are prone to foot rot, an extremely nasty fungal infection, so their cage must be kept clean and dry always. Dry food should be made available to them at all times. Too much canned food rots their teeth.