This could require a tear down of everything to the studs. Low levels require you to inform the renter. I know a family that moved from a rented meth house recently. They had kids and didn't want to deal with any possibility of health concerns. They were allowed to break their lease because the results of the meth tests were not disclosed.
They found out it was a meth house when "weird" people started showing up looking for the previous family. They got suspicious and either asked the landlord or got the information from the city. I can't remember.