In Michigan, you need a court order to evict a tenant; even with a valid lease. A non-standard lease is still something of a lease contract even without the address, as it states names, amounts and a time frame. And the lease does not appear to restrict the number of people who could live in the house, so it's doubtful you can prevent the boyfriend from being there.

Go to your local county courthouse or Sheriff's department and ask for information on the eviction procedure. You need to carefully follow the procedure for giving the tenants correct written notice via mail. Depending on local/state laws, you *may* be able to have them evicted in a few days due to damage. Otherwise, an eviction process can take weeks to months, especially if the tenant knows how to fight eviction.

But follow the law and don't lock them out and don't attempt to prevent the boyfriend from being on the property; they can take you to court.