March was almost scary good, several move-out's canceled to extend leases and we experienced higher than usual payments, a good surprise but one wonders if it's the calm before the storm. 

I was very fair and reasonable and even friendly and calm, but I would have immediately gone to hear the noise for myself and if it was bad and didn't sound safe for me to knock on the door, I'd call the cops myself. 

I just suggest you calmly and respectfully go see him and tell him that he knows you're going to have to kick him out and ask him how do we do this in a way that leaves my place un-trashed and he gets his deposit back?  

@Matt Higgins calm down it is a mouse, not a mass murderer, you have done more than enough just give it time, the mouse may have left or eaten some of the poison and died somewhere you'll never find it, or it was eaten by an owl, or cat or whatever.

He squawked a bit but calmed down when I showed him that his rent didn’t really increase.

I cut the conversation off and said I wasn't going to listen to that and if he wanted to speak to me about it when he was calm, I would listen. 

Is its demeanor calm and relaxed, or does it lock eyes with you, tense its body, and growl?

So, I calmed them down and told them if there was an emergency sewer problem, it wouldn't have been working perfectly for the last month.But, it took a while to get them to calm down and show them that they'd been played.  

Caverns, waterfalls and 2 active volcanoes that provide winter sports venues are a huge draw.

No need to be a jerk, but you can stay calm and have a friendly demeanor, the entire time you're calmly telling them things they don't want to hear lol.