In Illinois, I have seen:a park sold where the city would not allow the transport of homes in or out of the park;a park sold where the water was contaminated by radon that required a $2,000,000 fix;a park sold where the city was within 45 days of a condemnation order.All of these were sold to out of state investors who had not done enough due diligence.

My attorney suggest us to demand seller to complete oil tank removal prior closing the property to protect us from potential big ticket repair cost if the soil contaminate or someday the town mandatory request all property remove oil tank.    

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.

They are required to qualify the scope of lead abatement for contaminated properties and clear abatement projects when completed using the inspection and wipe tests.

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

Online resources provide by the state should be able to indicate if the site is contaminated.

Lots of industries need to do observations for maintenance, contaminated areas, tower inspections, oil & gas, marine uses, security areas, the list is endless, large companies will have their own but small ones or contractors that have limited uses may rent or hire an operator.

http://www.doh.wa.gov/CommunityandEnvironment/Contaminants/DrugLabs

There is no documentation or list of addresses with meth contamination that it appears on, as it was removed after the remediation, which is supposed to give the house a fresh start, at a cost I believe of $18K.

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.