Connecticut housing judges usually frown on this kind of behavior from tenants.Be careful, if your tenant's heat has gone out AND the temperature in the unit has dropped below a certain temperature (usually 65℉) the property could theoretically be declared uninhabitable.

Having a history of mental illness doesn't necessarily mean that the tenant could become a problem, especially since he/she doesn't appear to have a history of problem behavior. 

He certainly has a right to expect certain behavior like illegal activity won't happen but he has to trust her when she is out of his sight. 

Classic troll behavior in this thread, Karen nails all of the Greatest Hits:- Comes looking for help, starts by belittling a polarizing group of people (realtors) in hopes to drum up support for her cause- deflects any and all blame or responsibility for her situation- quickly realizes that everyone is not on her side- offers support and kindness to those who agree with her plight- constructive criticism or actual actionable advice is met with personal insults, threats of physical violence, and questioning of one's political affiliation- ironically insults the intelligence and/or grammatical shortcomings of 'detractors' in several overly wordy, poorly written, and grammatically unsound posts.- mystical tales of connections with untold wealth and previous successes rendering the opinions/advice of her detractors moot.- continues to be blinded by how her attitude and behavior are the primary cog in this.Me:

There was a movie called "Animal House" - crazy frathouse  behavior - that is one explanation.

What is the liability to the home owner if I put a specific clause in the lease regarding pet behavior and owner responsibility.

It is entirely possible that the move itself into a new environment triggered this destructive behavior which the owner absolutely has to correct.  

I know you are not alone in your attitude or thoughts to such matters, and that is exactly why we have laws, to ensure that landlords follow the norm of accepted behavior.

The late rent payment fee is for incentivizing the tenant towards good behavior.  

If you don't hear from her, you'll just give her 24 hours (or whatever is required by your law) notice of when you will be entering.Remember that her behavior is unacceptable.