Even learning the subtle differences between different states and regions is a huge learning advantage.  

Adrien Schebott, you could always agree to subtle renegotiated terms by amending your agreement such that the tenant gets another 10 days to complete a purchase in return for you getting a property inspection should he fail to close. 

Very nice touch for a C neighborhood.Paint the walls a subtle greenish/gray.

Some operating agreements will say that any cash flow to the investor first reduces the investor's principal, thence it credits toward accrued preferred return, thence you enter split territory.Other operating agreements say that OPERATING cash flow is first credited toward current preferred return, thence to undistributed accrued preferred return, thence you either reduce principal or enter split territory (one or the other)...and any CAPITAL EVENT cash flow (refinance or reversion proceeds) first reduces principal, then preferred return and so on.While subtle, there is a difference. 

You're missing the subtle points.  

I know how to spot some of the more obvious, glaring problems when walking through a potential investment property, but what are some of the more subtle things to keep an eye out for?  

My Leatherman is more subtle, but usually works.

It doesn't talk about the VERY subtle differences between capital improvements vs Repairs & Maintenance.  

Subtle detail pieces have always worked well for me.  

In Mark Manson's Book The Subtle Art of Not Giving a F**K, Mark describes only giving a F about things you know you are willing to suffer for, and knowing the level of suffering you are willing to endure.