Not being a lawyer, and not giving legal advice, as I understand it, you will have to give 60 days written notice to move if he doesn't move voluntarily. Without a lease he is a month to month tenant. If you initially had an agreement that he would pay rent and he defaulted you could evict immediately but if you let them live rent free without any kind of rent due, then you have a tenant at will and you have to give 60 days notice to change the current agreement or end the current agreement. Talk to a lawyer and confirm this before you do anything, but I think this is what you are going to find out! Sorry to be the bearer of bad news!