I suspect drug activity in one of my apartments and would like to know if it is possible to run a drug / chemical test to expose the situation.

(I know that I can learn everything for free in the BP forums, but for me it is worth the money for a little more hands on training, and more importantly speeding up the learning curve)My opinion on this is harsh so I will not say anything.

In addition the plaster itself was a lot like concrete and eventually the chemicals in it would eat through the heating mesh or wiring connections.

@Ned Carey Hope that didnt' come off to harsh and get into trouble with @Joshua Dorkin  or @Jon Holdman  :) 

What I'm really worried about is that they have a child with respiratory issues and the perception/reality of soot and chemicals smells getting into the fabric couch etc.  

Those who actually need the therapeutic benefits of the chemicals in marijuana can ingest the product in another form.

Do I think losing your property and going to jail for this may be a bit harsh?

That does look like it could be the sheet of underlayment that is high and the door has scraped away at it - check the bottom of the door - it will have matching wear marks.If that's not it, then perhaps it was a chemical conflict... certain vinyl and rubber can often be incompatible when moisture is introduced.  

I'm coming across on the harsh side to make my point understood!  

Unless I missed it, did you first confirm that there is a boatload of equity and profit potential, especially allowing for repairs of a house that been vacant through a number of harsh seasons?