The solution to that problem is that next to our attic there is a small room with a toilet and a shower, which one of our neighbors owns but has not used for a long time.

If you can lower the sales prices and get out this is the easiest solution.

There is a solution though because there is Non/QM which offers a few programs like (1) year 1099, Bank Statement, and DSCR programs. 1 year 1099 is self-explanatory, Bank statement uses 12 or 24 months bank statements gross deposits and divides that income usually 75% over 12 or 24 months, and DSCR requires No income or job, it uses the rents of the property as income as long as the rent(s) are equal to or greater than the proposed PITI payment.None of the above Non/QM offer construction loans though so you will need to stay W2 or wait 2 years.

They claim a 35% fee on the first year's savings, only if they save you money.Also, I received from my mortgage company an email from "Incenter Tax Solutions" who claim to be a nationwide property tax petition and monitoring service.

Savvy listing agents know these are toilet paper.Honestly there just isn't a great solution for folks starting out with deals that Fannie won't touch... maybe that says something about just how risky it is to start with 202-level deals instead of 101-level. 

I like the “you can add a window unit” solution provided the AC is working to its best ability.

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.