It is calculated on the net income that an individual derives from a trade or business. 

You have 4 kitchens, at least 4 bathrooms, more roof, walls, flooring, exterior, windows, and appliances   You need to place replacement cost and expected remaking lifetime on each item to derive a more accurate maintenance/cap ex.

I am pretty confident I can find a deal that rents out >2X the P&I (which is derived from the 50% rule) but that 2% rule is tough... at least in WA it isAlso, duplex, triplex and 4plex units are overpriced in my area IMO (I can't see getting at least 2X P&I in my area) whereas some smaller houses with 4+ bd at about 150K could get me cashflowing but still struggling to meet the 2% ruleAny thoughts are appreciated!

Sometimes I wonder how some CPA's derive their info.

I derive significant personal satisfaction and, of course, a large portion of my family's net wealth from this work.

Never buy a multi family with the thought that the value will increase as the value of a multi-family should be derived by the income it generates.  

Bonus depreciation is derived from the portion of the property's value with a shorter useful life than the buildings themselves.

In fairness, my distrust of "coaches" is not derived from any conversation I have had with any, but solely on the premise of their business model.

Explain your formulasNot my formulas, I'm not nearly clever enough to derive them myself, but I'd be happy to point you to my sources Joe. 

We have derived tremendous value from the books we have been reading as well as the podcasts we have been listening to and spending a bit of time lurking around the forums.