Landlord Question and Answer Forum

Hi- If anyone has advice on this rather unique situation I would like help. I have a tenant who is basically using the rental as a hotel for his "friends". There are a variety of people that come and go on a regular basis, most of whom appear to be vagrants. I have a security camera in place which records the arrivals and departures, and often they are carrying personal bags, pillows and bedding. Whether or not there is an exchange of money going on (or other services) I do not know - though I do suspect, without any substantial evidence, illegal activities of various kinds. I have approached the tenant on this and he says he has a right to occasional visitors. There is a clause in the lease which states that he is the sole occupant and that subletting without consent is prohibited, but unfortunately does not define "occupant" vs "guest". So in this vague area (nobody has stayed more than four consecutive nights) I do not feel it's appropriate (or legal) to ask the "guests" to leave - they often come for three or four nights, then are not seen for a week, then return. To make matters worse, I live downstairs in the same structure, hear the "guests" at all hours of the night coming and going... and am finding it very difficult to live under these conditions. Fortunately, the tenant does have a 60-day no-cause eviction set to take effect in a little over a month. He has acknowledged this, but I give it only a 50/50 chance that he vacates on (or before) the date of the eviction - and I am very worried even if he does, there will be leftover "friends" in the house after the date. To make matters even worse than that (though not strictly relevant) he stopped paying rent last year. In the state I live in (OR), there is currently a moratorium on non-payment evictions. Questions: 1. Before the eviction occurs, are there any fair legals measures that I can take to prevent/mitigate my house being used as a hotel? Other than just complaining to him? What, in general, if anything, prevents this kind of activity in rental units under usual circumstances? 2. Is it wise to get all the personal information of the regular "guests" so that I can evict them too? My lawyer informs me that in the event of their staying I will need to evict them, but has not recommended that I get their information beforehand. Doing so may identify them as sublettors - in which case eviction may be more difficult. Any help appreciated! -Tim