My sister-in-law volunteers for an wildlife rescue in southern Indiana. They have a pair of mated tigers, a panther, a cougar, a couple mixed wolves, a bobcat, some type of egyptian sand cat (I can't remember the name), hawks, ground hogs, raccoons. deer and various others that come and go, including alligators (who in their right mind would try to keep an alligator in a northern state?). Most if not all the exotics were from people that got tired of the upkeep, mess and expense involved in keeping a wild animal. Most of the rescued native animals, they try to rehabilitate and release, unfortunately some of them become too used to humans or have never gotten the ability to care for themselves and can't be let go back into the wild. If you plan to get a fox, do a lot of research and make sure you can/are willing to provide for it for it's entire life and understand it will always have a wild streak in it.
Good luck.