Don't rationalize any numbers, or use anything other than cash (i.e. equity, appreciated gain, tax deductions, ...) since those other items are NOT CASH.3 - If you have a negative number, that means you get more cash back in your deal, within the first year, than you spent (so in this case...used)...and you have a winner.4 - If you have a positive number, that means you have spent money to buy this property...your money.5 - If you fall into the #3 category, you have recovered all your initial cash (seed money).  

Nor do they operate rationally 100% of the time.

(And what if I'm rationalizing away a red flag!

She didn’t get a rational seller. 

while i understand the answer will be different for each investor, I am wondering what questions I should be asking myself so I can come to a rational conclusion. 

Speculation isn't investing (it's guessing with style), and rationalization is very expensive.

Most empty nesters move out of the nicer parts of Nassau anyway because at some point you just can’t rationalize paying $35k a year in taxes with no kids in school. 

You'll end up rationalizing your way into bad (very bad) deals that will have a domino effect on all future deals. 

@Brian EllisThere is one major reason for thIs - your price is too high. stop rationalizing it and losing money waiting around .Drop the price and watch what happens

Stop rationalizing.. your price is too high so drop it