It also adds in your loans principle amortization ammounts each year and subtracts closing costs on sale to show you your total return. 

If a property backs a major road, you subtract value, if it backs a greenbelt you add value.

But if my equity gain significantly outpaced the rent growth, that means my equity is not working for me efficiently (ROE is lower than what I would get from a new deal after subtracting all potential costs), I may consider sell and exploring a new market / property where I can get even an even higher cash flow (of course, not a simple rent/price ratio consideration when choosing a market/property)..Would be happy to hear your thoughts too!

They typically do this by totaling theappraised value of their real estate and other assets, subtracting liabilities, dividing the result by the number of shares outstanding.

We then subtract our actual expenses, which include management fees, bank fees, appraisal costs, insurance, commissions, marketing costs, taxes, and legal and accounting fees.

Or would have been if you were single.DepreciationReal estate investors get to subtract an additional deduction: depreciation of their properties.

If I subtracted $1k/month off it would be $1700/month return on an initial investment of $47k.  

So, estimate what the value would be all fixed up, subtract the cost of doing that work to make it "market ready", subtract the realtor fees of 6%, subtract 2% concessions (on average), subtract closing costs, figure carrying costs for 90 days while waiting to sell and close, add MLS showing hassles, and you get an idea if it's worth selling "as is" or if you prefer fixing it up and listing on the MLS. 

If I subtract this $174k off my investment amount (down and closing) , the investment base amount is reduced significantly resulting in increased return.  

Most taxing districts subtract a percentage off the actual value of the property to not have so many people complaining about their tax valuations.