Do you have video cameras up in common areas or a vacant unit you could rent to a police officer? 

Reasonable accommodation may include waiving or varying pet polices and fees to allow an Assistance Animal.

It's in a nice historic part of town, couple blocks from police station, multiethnic, etc., but buyers are just not pulling the trigger.At this point I am probably just breaking even or perhaps going a bit under.

It's adjacent to a police station, near shopping, and near the high school.  

If that happened in one of my rentals - I don’t have enough liability insurance.Most of the cities around have list of prohibited breeds and one complain from the neiborhood- you’ll have to remove the dog if it’s acting aggressive and police was called on. 

Whatever happened to calling the Police ???

I guarantee if you were to call the police they would not remove them. 

First thing that came to my mind when you mentioned “illegal” was to have the downstairs tenant call the police.

Recreational use is hardly on the radar of police in our area and I'm sure it's similar in yours due to the aforementioned changes that are taking place. 

This guy who had been living with his GF on and off had some issues with another tenant in the building and apparently this led to police involvement one evening with allegations of someone shooting at him (the boyfriend of the other tenant is the alleged perp).