A lot of beginners often forget about holding costs (if I'm being honest, I still under-estimate sometimes!)

We estimate 3 to 4 times the amount of the loan by the time we plan to sell the house in about 5 to 6 years.

Property 1:Purchase price - $73,000Mortgage - NONE (Paid Cash)Monthly Rent - $875Monthly Profit - $580Property 2:Purchase price - $65,000Mortgage - NONE (Paid Cash)Monthly Rent - $950Monthly Profit - $750Property 3:Purchase Price - $107,500Mortgage - $80,625 Monthly Rent - $1300Monthly Profit - $435Current Cash Available - $110,000Current Available Equity - $96,500 Cumulative Total - $206,500The available equity was a HELOC loan that was given at 70% LTV so those are real numbers, they would be from property 1 and property 2.The reason im typing this is because I would like to know if there were any builders that could give a rough estimate of building cost per square foot in Kansas City area or suburbs.

Emory-The 70k valuation is a very, very rough estimate. 

And an infestation of German roaches that made the pest guy jump (he said).After everything was said and done, we incurred 4 times the cost as I was told/ estimated. 

From there, form an estimated replacement cost, and write down the estimated remaining life left. 

Advice: Reach out to your lender or someone experienced with streamline refinances who can help advise a more accurate estimate for you. 

Consider how long this might take, then double your estimate if you really have no idea.

Did a contractor provide the $40k rehab estimate?  

So how do the banks estimate OpEx?