Being from illinois, I do get a kick at how much regulation goes on out there in tennessee - where people give me guff about how our local politicians here are so intrusive. 

If you think there might be the possibility of development raising the value in the future, you could try renting out the property to others for non-intrusive uses - parking, roadside vendor, etc. 

If the mold is caused by a leaking pipe or water getting in from outside, then you should hire a contractor to stop that intrusion immediately, then dry out the home and remediate the mold at your expense.I also recommend reading and sharing the EPA Mold Guide.

If you have any further concerns about mold/fungus an industrial hygienist should be consulted.Grading and drainage is either negative (slopes towards the foundation) or neutral adjacent to the left of the building, and moisture intrusion will remain a possibility.

They are intrusive and long, but will provide all the financials, projections, demographics, financing, fees, insurance, etc.

Hey Joe, Flat roof leak detection can be hard because the leak may be some distance away from where the water intrusion shows up inside the home.

They can probably advise you on what to say and how to combat the intrusion. https://www.usa.gov/legal-aid

Any area of the home exposed to the exterior is at risk for moisture intrusion.

The remaining 15% only represent about 1,000 intrusions weekly! 

Cast iron waste lines become so tuberculated that waste can't pass through, or the joints fail and allow heavy root or soil intrusion.