Before you start singing praises for certain companies and what they sell you might find this interesting....http://saferchemicals.org/newsroom/new-study-finds-toxic-chemicals-widespread-in-flooring-sold-by-top-retailers/

Also, I know you already told them NO, but for future knowledge, never agree to any remodeling while a tenant is in a unit.....the potential of harm and lawsuits is not worth it. 

Pitbulls and other dangerous breeds will require risk insurance at a higher premium and will open you up to legal problems if the harms someone. 

You ARE responsible for the harm your tenants cause neighbors.  

If the building has 4 units or less and the landlord lives in one of the units.If the property is a SFH and the owner owns less than 3 SFH's.If the animal brings an undue financial hardship to the landlord.If the animal causes damages or harm to others in the building.

Being listed as an additional insured does absolutely zero harm to you, however it does protect you in the amount of the liability coverage on that policy and it also pays all legal fees up to the point when the limits have been paid out on the policy or the claim is denied.

Real risk of harm to others, not just defaulted rent and property damage.  

@Art Maydan 1). from an insurance perspective, you could be held liable if a tenant is harmed because of non working life safety equipment.  

Don’t volunteer to put yourself in harms way with the language you use to describe your relationship..

If/when they do nothing, have an attorney send a letter to the HOA notifying them that you will be filing suit against the HOA and Board members individually as their willful actions have caused you harm and try to get the HOA to enforce the covenants as your property value has been hurt.