When is it time?

This is a question I pose to all of you caregivers. When is it time to take away all of the freedom that a person with AD or any kind of dementia? Like the bank accounts... You take them over and they still have to put their fingers in it so things are not quite right, or you know they need to go to the DR. but refuse. The dentist, but they refuse. Takeing a bath and unless you are hog tying them down they are not going to take it. No I am not talking about you Joe. I also know that if things are not taken care of it is a form of abuse but what do you do?How do you deal with those issues. I know that they are coming for me and I can't hogtie Joe down. He is just too strong for me. This is something that I would think all caregivers deal with at some point. When do you put into effect the POWER of attorney and tell them that they can no longer make any decision? It is sad that they are losing what they are and knowing it but when do they not know anymore? Input from all of you would be good because I will be needing this information too and I am not looking forward to it. This will be a battle of epic porportions when I do.
Take care