For now I don't think it is necessarily a problem since those seems to be out of sight from the property and there is no disturbance such as noise/smell... but I am curious if anyone thinks otherwise?

Sometimes they have fights and break stuff, or shout at each other so loud that it disturbs the neighbors.  

His theory was the worst condition was to have wire getting hot and not being able to adequately dissipate the heat, especially if there had been traffic in the attic disturbing the wiring.

It can also be from a social worker.You cannot require a person with a disability-related animal to have renters insurance unless you require all tenants to have renters insurance.I recommend having an Animal Addendum that applies to allow animals and your requirements regarding property preservation and non-disturbance of other tenants, along with consequences.  

As far as the STR issue - I would not want to offer that if the threat of someone from zoning may show up at the door and disturb renters.

This is what really disturbs me. 

If I have a prohibited conduct clause in my lease which states that "the tenant cannot disturb, threaten the comfort, health or rights of others" can I use this as a basis for an eviction if the tenants animal lunged at or attacked someone with the assumption that there is no prior history of the animal behaving in a threatening manner.

The asbestos will release if the insulation is disturbed, so any form of you picking it up, moving it, etc., poses a risk of it going airborne.

I ideally do not want to disturb the tenants with an appraiser. 

It is imperative that you trusttheir decision in regards to their job duties.If you need to discuss a more serious matter, then have a meeting (whetheryou are husband and wife, or in a partnership)I’ve touched on some very disturbing things about this business at thebeginning of this book.