Does the animal perform a task, provide a service, or alleviate symptoms related to the disability?

Be firm in requiring proper documentation, but there's not much you can do after than until you can demonstrate that other tenants are negatively affected (ie allergic and having symptoms) or the animals are doing damage to the apartment

They just started feeling sick for a few days, then finally a friend recognized the symptoms and they had the fire department over.

You can go online type in what the "symptoms" are but don't tell them you know what is really going on...let them tell you.

If there's no rust or corrosion or any other sort of water damage on the electrical components then I'd say leave it be... it's leftover from a previous symptom.

The majority of the time cracking and deflection is a symptom of external issues happening around the property.

It is an animal that works, provides assistance, or performs tasks for the benefit of a person with a disability, or provides emotional support that alleviates one or more identified symptoms or effects of a person’s disability.

We used to have lots of different business cards, that we laughingly called "symptoms of our disillusionments".

The CO may just be a symptom of bad fire caulking/sealing in the garage. 

To me, the interior systems are treating a symptom not solving the problem - you need to keep the water out of the house in the first place, not just get rid of it after it comes in.