Does he have a handlebar moustache ?
Just make sure that you tell people so that when you go missing the cops have a lead.
I would be
Why? They seem like cool people.
Does he work or socialize ? I would be worried if that's ALL he did, EVERY day. It's not healthy.
I told you to leave me alone! I didn't steal your beers for crying out loud! and it's not heavy metal it's death metal!
Amend you rental agreement to stop noice of any type after say 10 PM. In the mean time ask the renter to lower the music cause it is bothering you. Another word you can use in the rental agreement is NUSANCE, because a legal judge will accept it for removing the renter.
Only if he starts spouting KKK rhetoric or talking about building a motorcycle.
Not at all...he sounds like a fine, upstanding citizen.
Is he wearing leather
it all depends on other conditions. does he work? is he on other drugs too? is he in a cult religion? ;-) you see what i mean? image and behavoir are a couple things but it's deeper than that. if the guy creeps around late at night with butcher knife after going ocd on van halen's "running with the devil" then i'd have a talk with him.