Uhm, I don't know about where you are, but here, to evict a tenant, the owner -must- have a valid reason in which the tenant has not respected the conditions of the lease. And a decision from a governmental organism that acts much like a court.
Actually, I'm not even sure it's legal to refuse the renewal of a lease without a valid, verifiable reason.
I'm completely ignorant of laws where you are, but look them up. Call a law help office (you do have free lawyers for the poor, right?), or something. I seriously doubt you can just kick people out when you feel like it, even in the Unreasonable State of Affairs (USA).