@Mike Hartzog Thanks for the data point.

I would start with this before digging up the yard given it wasn't leaking before. http://www.xypex.com/docs/default-source/product-data/patchn-plug-NA.pdf?

I've been scoping the neighborhood scouts data and things SEEM appealing but I have a gut feeling that crime over there is b-a-d. 

As an appraiser I can tell you that the estimated market value in an appraisal is only as good as the market data that is readily available. ie. comps...the problems with appraisals, which there are many, is that you are always looking in the rear view mirror at historical data...just like anything in real estate, local knowledge is also better than not, meaning that an appraiser who lives and works in the market area is better than someone coming in from 15 miles away and has no idea of the marketplace...I have seen appraiser come into my area and be off by $100k in value (on the low side)...just like anything in this world, there are hacks and there are true professionals...appraisals are a roll of the dice I'm afraid...just my opinion !

Rental cash flow is evaluated by an APOD (Annual Property Operating Data sheet).

I just wanted to post some data to back up that trash talk!

You don't learn you market entering data into or reading a spreadsheet.

However, in my opinion, 10% should also incorporate bid coordination, bill collection, rent collection, bill payment, financial data collection and recording, lease inquiries, showings, Subsidy / City inspection coordination, etc, etc.  

Go to your local county office and figure out how to get data on unlawful detainers, notice of defaults, divorces, death certificates, Quit claim deeds, back taxes of 2 years or more and code violations...start building those lists and mail to them consistently.If lawful, put out at least 25 bandit signs every week.  

On the other side, city-data says that medium income in that zipcode is about ~40K, which is quite low.