They did try on the convincing like you said...and yes she is mainly a residential realtor.She said there was $94,000 in NOI....she literally subtracted out taxes and insurance from 100% gross rents...lol

I also asked for the previous utilities and the seller sent a word document saying Gas 310 per month, electric 275 per month and water 175 per month .multiplied those numbers by 12. gave me that as expensesthen took his rent income (all 10 units) multiplied those out for a year and said income. subtracted and said profit. 

Subtract mortgage and taxes ($4560+$1300).

To do this subtract price of land the house is on, and divide by 27.5yrs to get yearly depreciation amount.Taxable income = Rent - costs - (50000 - land )/27.5Then this amount is taxed at marginal income tax rate for federal and state.

Subtract the service lease and typical 50/50 split and . . . just so questionable.Ignoring laundry, GSI is 68,700 and using a GRM of 10, the FMV would be in the neighborhood of $687k. 

In order to quantify rents I checked Zillow, Craigslist, etc and subtracted a couple hundred off of what 1 and 2 bedrooms were asking there in the area.

Offer 55k    (75k is the 75% of ARV and subtract 20k for the rehab, etc)

Then calculate your maximum offer price by multiplying the ARV times your required discount and then subtracting rehab. 

So, what is your Cash Flow number you like to see after applying the 50% rule (and subtracting mortgage payments) to motivate you to move forward or lock down a deal?

Sell for 350,000 = 50,000, then subtract out closing costs, etc = 40,000. b- adding a second floor to it.