Answer: My first question is, are these guests showing up at the invitation of your resident? Secondly, are they creating any disruption, or bothering the neighbors? Have neighbors complained, either to the resident or management?
Having visitors viewed as undesirable by management, or even by other residents, but causing no disruption, is a difficult issue to correct, assuming their presence is with the acquiescence of the existing resident.
To put this in a legal perspective, since for a lawyer, that is the litmus test, what is the violation? Is drug dealing in the neighborhood suspected? Do these visitors have outstanding arrest warrants? Do they have criminal records, and if so, do they relate to violent crimes, sex offences, etc? If you suspect illegal activity, I would contact the sheriff’s office to see if they can help identifying the visitors to determine criminal backgrounds. Certainly, if they are dangerous ex-felons, or actual drug dealers, for example, you should want to know sooner than later.
However, remember, since these folks are just visitors, and not permitted tenants or occupants of the space, any violation would have to issue to your (formerly) good tenant. If this is a question of the visitors’ conduct being disruptive to current residents (e.g. under the peaceful enjoyment statute, ORS 90.740(4)(j)), you would have a basis for issuing a 30-day notice under ORS 90.630(1).
But before doing so, I would suggest that you contact the resident and have a private and frank conversation. It may be that the resident is just as uneasy about the visitors’ presence as you, and would welcome your request that they not visit with the frequency they are.
Last week’s article addressed issuing a Trespass Notice. If your resident is prepared to ask his relatives to discontinue their visits, then you would be within your rights to issue a Trespass Notice, should the visits continue.