The Metroplex is all clay-based soil. 

Where he was talking about using a big straw to drink the oil from underneath that preacher's land. 

It is a raised foundation and all sand underneath.

I thought ok they are local so il keep an eye out for them and at least be aware.So i get there and sign in thinking okay let's see what this is about and network with some like minded people.

There are a lot of other inspections you can do (soil tests, etc), but the above is what most of the investors we work with do. 

How do you determine the value of the land underneath, from the tax assessment, or from whatever is agreed upon?

Or, I can plant a garden across town where there is fertile soil.

(The soil moves a lot in Texas)Like any deferred maintenance (roof / plumbing / HVAC) it's really not a big deal as long as you know the problem exists, get good quotes for repairing it, and incorporate it in your business plan.

New regulations can make it very difficult to renovate or otherwise develop a property.Sometimes you may discover that a property has or is near a sight with contaminated soil.

There are many other factors that could have contributed including insects, rodents such as ground hogs, weather, poor soil quality, etc.