I mentioned that while I understand the need for a vent, if it creates noise and disrupts our sleeping, then he would be responsible for remedying it. 

And if you happen to screen poorly and install unfit tenants, that commute will continue to disrupt your life and your kids' lives.  

My thought was similar - if we did have to compact, it wouldn't be all that disruptive.

Since so many are demanding one party to do the work of what used to take multiples, old business models in real estate are absolutely headed for a major disruption.

They are disruptive tenants, now you need to confront or pay to tow them?

You can ask them to also move the tenant from your apartment because of the disruptions with other tenants and personnel. 

You could find a syndicator like Grant Cardone and go on a multi family deal and get great returns without disrupting your life. 

How can they allow a resident to bring in a new animal into tight living quarters without knowing if it barks all night disrupting everyone, whether it is aggressive, whether it listens to the owner? 

As a property manager for a few years now I can say that:1) it's incredibly rewarding and one of the best feelings is to take a problem property with problem tenants and turn them around and make them into a profitable venture (I've been doing that for a decade with foreclosures so it's much the same to do it for investors).2) I have fired clients over the years...when my office is disrupted and angry emails and calls are coming in OR when I have come to the conclusion that an owner doesn't feel we are worth the value (and in turn we don't feel they are worth the effort to calm down and constantly smooth feathers) then we respectfully part ways. 

I'm sure you can hear the train, but not to the extent that it would become disruptive if you were hanging out in the yard.