The things that the normal and regular science is unable to explain other than assuming its own rationality

Hi Sean,Living for free seems to me like a rational choice.If it were me, I'd pay to have to have central A/C put in simply for my own comfort.Good Luck! 

It's a simple math problem, that you will see over complicated with rationalizations when the simple math doesn't validate a property as being a good deal. 

", are all rationalizations for a bad deal. 

If I were to live in it for good for sure, I wouldn’t mind doing it up but there is a good chance I may have to rent it out until I am ready to retire in which case no point in dropping a lot of money now, I may do it right before I move in at the time of retirement.On the other hand, with those views and location I feel I could potentially fetch decent rent if I do it up nicely.what other objective criteria I should consider to make a rational decision?

Keep a dated journal of your experience, install a security camera for video evidence.Make all interactions with him in writing, and always write your interaction as if a judge will read them 6 months later, don't antagonize or be passive aggressive, just factually state the problem and your reasonably requested solution, in a polite and neutral way.of course, none of that will probably work, but, it will be proof that you were reasonable and rational about the issues and it will probably show the neighbors antagonistic demeanor.Be real careful, that is real crazy to get a fan to intentionally blow smoke towards you.

Because we human beings aren't rational in any stretch of the imagination. 

The more knowledge one has specific to locating deals, turning bad deals into good ones (without rationalization), and finding the sources for these deals where there is little if any competition, is worth that pot of gold at the end of a rainbow. 

If you don't have rental income on your tax returns the banks may only count a portion of the new rental income toward the debt coverage ration (Net income $ / Mortgage $).

Rational thinking and logic are not their strong points with these conditions !