Information about Ferrets?

Alright, me and my parents are considering getting a ferret. From Petco I know they are descented and spayed/neutered. My mom had a bad mishap with a ferret at one point, but I know that not all ferrets are aggressive. I use to watch my neighbor's ferret from time to time, he was timid at times, but extremely friendly. I have also heard that ferrets can almost be like having a puppy or a kitten for 9-10 years, and thats what my parents might like. But I was wondering if some of you could give me more info on ferrets, like how big of a cage do they need? Best food? Shampoos? Size of a playpen? Can they run around a room if the door is closed? Do they chew on furniture? What kind of toys do they favor? Any info will help. :)