If the house is old you could have buried oil/gas tanks leaking..  

With all the layoff in Oil and Gas right now i was forced to pay more attention to my job while still have to keep an eye on all the current rentals, while expanding the portfolio. 

The giver's perspective may have been once valid, for their zips, deal type, price range and most importantly for their period of time.  

But other than gas and mortgage they didn't spend much money for something like 20 months.

There was a strong gas smell in the house today (which is being investigated) and that made me realize that we don't have CO detectors in the house and should.  

So, you can make money as a lead generator / bird dog on a few tanks of gas.

That is a very valid point.

You validated most of the criteria I've been using but I wasn't aware of the export functions before purchase! 

In any case I *do* get your point with regards to my misuse of the CAP rate :).A more valid/normal use of the CAP rate would be if I turned it around and imagine that an investor would want to to buy my portfolio at a 7.5, 8 or 9 CAP.

Tenants are paying electric and gas only.