Well, I guess I don't have to tell her, she read the post before me!
Anyway, in answer to your questions:
1. Yes, you can use home, or 12 for the POS
2. Coding would be the same
3. This is not a clear cut answer. There have been other posts on this as well. Some say it must be left blank, others say to use the office address there. I think it will depend on your area, and the individual carriers.
4. They can bill for PT in the home, if the patient has the medical necessity.
Hope that helps.
Michele