To top it off they have a jury rigged above ground tank that feeds it or used to feed it.

A cookie cutter builder would not suffice.

There have always been oil companies in the area, but roughnecks are not ideal tenants and  there are also dozens of rigs laid over in the yard right now.

Is not a cookie cutter, you will have good reliable tenants, and sometimes you just don't. 

They were side by side cookie cutter homes. 

I would invite the Buyer & Buyer's Agent to be present while the test is being conducted to show you are not trying to "Rig" the test. 

(Be very clear here... this does not include cookie cutter homes in the suburbs where those big juicy commission are hiding) This one gets the conversation started and gives you an opportunity to see if the agent can talk the talk and back it up.

While this works for experienced and knowledgeable investors in cookie cutter residential SFR, not so much in land and commercial property.  

If its boiler plate cooky cutter it will never hold up.  

These were post WWII cookie cutter ranches built in greater the Boston area.