That is not investing it is hording.When you buy with cash subtract 10% off the top of your rental income, before any other expenses, to pay for the return on your cash invested.

If you move to another location and want to use your "second tier" or "remaining entitlement" you will look at the cap for the area you are moving to, then subtract the amount of your first loan.

You have to take it with a little grain of salt when you do that, but if the market hasn't shifted a lot in that time period the numbers should still help.The other option is you can look at houses currently listed, but you should probably subtract about 6% or even a little more for realtors commissions and the fact that it will probably sell for under listing (unless it's a hot market that usually sells for more).Lastly, as Christopher said, you can just go with different beds and baths and try to adjust, but that can get sort of tricky too.None of these is as ideal as your original method, but I work them in the order I listed here and just do the best I can.

Your profit positions is determined by taking your purchase price (85K) and subtracting depreciation (The structure value/27.5 x 10) ish.  

I subtracted the water bill from it.

The title company should subtract that money from the final transaction between the seller & the buyer I sell the contract to.

I just calculated out what 6% would be, divided by 12 and subtracted the 4% rate.

I typically subtract 3%, of the ARV.Realtor Fees: What is the commission you are willing to pay your listing agent (unless you are the listing agent) and the buyer's agent.

You must take the total monthly rental income and subtract the total monthly operating expenses to establish your Net Operating Income (NOI).  

Say you can spend 1k to fix up the apartment and rent it out for 500 a month , you may want to add in a little for that or maybe not , or you might even need to subtract more off the price if it needs extensive work.