After talking through it with our broker, the red flags are really a measure left over from the 2008 bubble that prevent flippers from speculating on properties.

Measure twice, cut once.

where they talked about sub metering companies that install sub meters to measure what tenants are using then bill the tenants for the utilities directly.

For those of you investing in 2-4 unit properties...do you weigh one financial measure differently...or do you just look a basic ROI...or CoC...do you find IRR or MIRR relevant?

What are the due diligence measures to take before buying this property.I am novice investor but hoping to rent it fully in a year or so and sell it for profit.  

I spend a couple of hours taking photos, measurements, and notes.

Last but not least I love the fact that you can actually measure and predict returns in ways that are far easier than the stock market. 

After measuring the interior square footage with my contractor we found there is enough room to have 3 bedrooms (10 x10 ), (10X 10) (10 x9).

Population growth is an easy number to measure and verify.

Thank you for your post @Chris K. and for the examples. yes, i understand that the GRM don't show the NOI which we can us to measure the cash flow.As you alluded to, It is often that we see that MF in desirable prime areas selling for low Cap and often the same as houses, this is often do to the properties been attractive to home buyers.