I have a roommate that I want to leave he does not pay rent but has live here rent free for years. I own the house and I live in Los Angles California. I have just retired, and he is an older man 75. I have asked him to leave and he won't. What can I do?

This man may be considered a lodger. In which case you can hire a sheriff to remove him after giving him 30 days notice to vacate. If he doesn't qualify as a lodger, you still have to give him 30 days written notice then take him to court for an eviction order.