Simple solution: Inform them that unfortunately you can’t accept ESA letters without being able to verify the validity of the letter by speaking with the local licensed mental health professional who prescribed them their ESA, so that you can verify that they have a legitimate disability requiring an ESA as well as that whoever prescribed it to them is a real licensed mental health professional who has an ongoing relationship with them beyond just receiving a one-time payment to “prescribe” the ESA. 

The problem to the solutions of having a window AC or portable on standby is that if your portfolio is large you will have to have $10s of thousands of dollars of ACs for "just in case" moments.

I personally prefer to be more on the advising and relationship side so I can give my clients more tailored solutions, help them avoid pitfalls, connect them to people that can help them grow and structure their portfolios and I treat this industry more as a relationship business rather than a transactional business. 

There are a few issues and solutions that I can think of, and some were already mentioned by the other investors:1.

I was an agent when buyer broker agency was introduced in VA, as a solution to avoid the many lawsuits post-sale arising from buyer confusion that the agent assisting them actually represented them, when at that time all agents worked for the seller.

Is the camera set up to point at their car (ie the tenant who owns the camera is using it to monitor their car) or to point at the other tenant's car?

Even if I wasn't I would still suggest doing it yourself, great way to monitor the business.   

The vision of this program is to help the investor determine if it is a viable file AND to monitor the property’s investment value after purchase.

When I worked with them, they were extremely reasonable with their borrowers when credit was not available to figure out working solutions, which steamed from the due diligence and experience they did on the borrowers.Corey Dutton, DFA does not prevent HML on primary residence, it does put rules around loans as they relate to primary residence.

I think this will be a great solution - just in time for fall!