Yes there is no law
legally you can not give a 15yr boy permission to move out. if you are having problems with him get help. it is still your son!
Yes, you can give them permission to move out. It will not remove your responsibility for their welfare.
No, you are not.
You would have to convince them to move out. If they don't want to leave, it can be pretty difficult without help.
If you own the house,then why not?
you have to get permission from your dad.
You'll need your mother's permission.
Of course that's having sex with a minor, 17yr old is the legal age now so that's considered statutory rape!!
If you have legal custody yes.
Unless his son is legally not able to make financial decisions on his own, his son must sign the policy as well.
Many places allow you to legally "divorce" your parents or children. If your son is legally an adult than you should be able to do this, if not, don't bother.
Depends where you are. Here in the UK the answer is yes.