So, the formulas simplify to:Cash Flow = (Rent - DebtService - ManagementFee - Insurance - RealEstateTax - PeriodicFees) x (1 - StateIncomeTax)ROI = (Rent - DebtService - ManagementFee - Insurance - RealEstateTax - PeriodicFees) x (1 - StateIncomeTax) / ( DownPayment + ClosingCosts)We perform a multi-step validation process for each property, adding more cost elements as we gather more information about the property.Comments:We do not include depreciation because the amount people actually benefit from tax deductions depends on their unique tax situation.We do not include unrealized gains, such as principal paydown or appreciation, as they are only recognized when the property is sold.

In the past we have used Sage Accounting which we use for our 'day job' business but are looking to simplify things and make it accessible to all three of us remotely also.

@Josh Smith - Unless you want to allocate every expense, you could take the simplified option.

For a simplified example, say we have a 10 tenant building and each tenant is renting the exact same square footage.  

To make my life easier, I am planning to build an app to simplify cost segregation for small property owners just like us.

Either way, simplify your life.

It can get complicated on the property taxes so I will just give one very simplified example:A man bought a house in 1980 for 100k and his current assessed value is 200k due to the homestead exemption which allows a benefit of a maximum increase of 3% per year in the ad valorem tax portion of the property so now it is assessed at 200k.

It has really simplified rent collection for me.

The meetups are called "Simplified REI" if you're interested and have trouble finding them feel free to message me directly. 

Maybe our way is over-simplified by your approach, but we are not pulling credit on our tenants like they are buying the house like you are.