From what I understand...kitsune are supposed to be able to take on a human form once they have enough experience, though a lot of the time they're supposed to place something on their forehead in order to transform...a broad leaf, reeds, or a skull are common, and their shape isn't limited to their own gender. They can also assume the shape of a specific person.
Kitsune also tend to have a fear or a hatred of dogs.
Possession as an ability isn't particularly rare...a kitsune is supposed to be able to possess another human, usually a young woman, entering either beneath the fingernails or through her breasts, and their facial expressions often change to a more foxlike one.
In some myths, they've also been known to:
-enter people's dreams and manifest there
-fly
-become invisible
-create illusions so elaborate that they're indistinguishable from reality
-feed on the life force of human beings, typically through sexual contact
Another note, nine-tailed kitsune are generally supposed to gain the ability to see and hear anything happening anywhere in the world...though some myths have expanded this into actual omniscience.
Edit: You may also be interested in checking out
this site, specifically
Japanese Fox Stories and
Common Misconceptions About Fox Spirits.
Edit Edit: Not that accuracy in kitsune myths is necessarily what you're going for, it would seem...but it
is interesting. At least, to me.