Hey, it's perfectly fine to have ferrets outside, our five are happy out there all year around, they have pretty much what you described above. our's are on concreat although at the moment they have some top soil and shavings in there, i try to vary textures, they had bark a few months ago.

the only trouble I tend to have is fleas but i just spray and bath them ragularly, also i worm them every three months like a dog/cat.

Also, are you only getting the one? or are you thinking of getting two so that they have company 24/7? they like to snuggle up at night together, well more the day they're often playing at dusk as that's when their natural prey would be out. Plus it does get cold in winter and you may not want to be outside for a long amount of time.

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