In my own experience:

1.  Totem animals are tribal and it is a Tribe that has a Totem animal, not a person, or rather it is the Totem Animal that picks the Tribe.....
2.  A power animal is personal and not necessarily a guide.
3.  A guide animal is personal and not necessarily a power animal.
4.  Power Animals tend to stay with you as long as you need that specific kind of Power...
5.  Guide Animals stay with you as long as you need to learn a specific lesson. (Some stay permanently)
6.  Power animals tend to come from the Lower Spheres
7.  Guide animals tend to come from the Upper Spheres
8.  You cannot really upset a Guide animal
9.  You CAN upset a Power Animal, and it is NOT recommended ....LOL
10. You are also right in saying that no one can "own" any of these creatures...

The rest is a little off topic and about becoming a Sangoma (African Witch doctor), a Medicine Man/Woman (American Indian Tribes or a Shaman (Siberian Tribes)
so I will not talk about this here...but if someone is interested we can open another thread for this purpose....

love and rainbows

Raka