The roommate who is the lease holder signs the roommate agreement as the landlord, and then has the authority to issue 30-day notices to the offending roommate(s). "After talking to many apartment owners, they would definitely prefer this arrangement, as they only have to deal with one person for the rent money, as an example." But not all states and jurisdictions permit this arrangement (e.g., Florida); check with your local housing office before counting on this safety net.