Get tight as bark on a tree.

This causes my dog to be extremely restless and constantly barking at the walls when the vermin are active.

The tenants down below can hear all the dogs barking and running around very easily which makes it a noise and nuisance issue for the tenants below.

Well you don't want something like a beagle that has a penetrating bark.

MFs are priced too high in my area, exit strategy is limited to cheapskate, low-ball investors like yours truly, and I don't like "my neighbor's dog barks all night" phone calls.While MFs have their place, there is always a strong demand for a house with a yard, especially for people with pets. 

We haven't even mentioned bed bugs, roaches, rodents, noise/disturbances/dogs barking, people who aren't residents dumping couches in your trash bin, litter, animal poop...Multi-fam can be profitable, but you run it like a business, not a "Mom and Pop" shop. 

Did it dig up the yard and bark at the neighbors all day?

Things like, how furry (i.e. sheddy), does it bark, does it tear things up, how well behaved, etc.You don't have to set expectations for potential tenants, only for the tenants you place in there.

Some scratch doors or bark incessantly.

I stopped by some of the old neighbors only to find out that the new tenants are holding the neighborhood hostage by calling the police on the older gentleman next door because of his dogs barking.