I have a building occupied by several tenants each with a commercial lease. One of them hasn't paid his rent for 4 months, and while I have tried to be patient with him I am now ready to get rid of him. The other complicating factor is that his lease isn't signed so I don't know whether the terms of the lease apply or whether he has some other rights at law. I know that tenants generally have more rights than landlords under the law. What steps do I need to take to evict my tenant that's not paying rent and get the money he owes me?