Yes, there is a risk that their value quickly falls in a market crash, but I feel that statistics are on my side, and that I can make up for that risk by having a large amount of money in relatively liquid index funds.

Been in this business 15 years, and seen the good, the bad, and the ugly ... watched all those newbies shoot past me by playing aggressive in 2007, only to watch them fall and I blew right past them in 2009.

The one deal that I had did not fall through (owner backed out for "personal reasons").

I understand real estate, how to negotiate and what makes sense... but math is where I fall apart.

Be there when you need to be there, immediately, in a case of fire, of hurt and fall.  

MIP doesn't fall off and is for the life of the loan, where PMI falls off.

It did fall under nuisance activity, in my mind, but they were also shooting the clays over the neighboring property. 

You have to remember "extra" costs such as snow plowing and grass cutting that fall on the owners.

Also worried that what if the next loan down the road falls through, how is that rent paid.

Redfin says it's pending since October, did that fall through?