You may be able to go with smaller lots since no worry about water well and sewer leach field contamination.  11.  

My suspicion is, the dead guy won't bother to redeem the property.My main concern is environmental contamination.

This short-term airing-out may not be enough to clear out all the contaminants from the air inside the home.

@Michael Knaus I'm straying a little here but that insulation in question is likely vermiculite - not the pipe insulation which is a different use of asbestos.https://www.epa.gov/asbestos/protect-your-family-asbestos-contaminated-vermiculite-insulation

Since the new tenant is a "dentist" , the water and other contaminants to the floor  might make it wise ti go with a commercially rated hard surface for the operating rooms and labs with carpet in the hallway, waiting areas and staff areas; reception, private office.

Notable exceptions are contamination risk and possibly a few others.I guess this thread is a good example of what makes for a market!

Second, if meth was involved or suspected, you want to make sure your house is not contaminated.

What I don't know is whether it was like this every summer before and the tenants just didnt care...The poor bastards at the HVAC company have cleaned the coils multiple times, checked the pressures, and at their last visit emptied the entire unit of coolant, put in a new pump just in case, and then weighed the coolant back in to make sure there were no contaminants.

Low and behold soil contamination was found.

Additionally, you could offer to place an Ozone generator in the house directly after the hour-long 'inspection', for an hour or so (this will kill/de-activate just about anything airborne in the house), to eliminate any remaining risk of contamination.