I know Bed Bug issues are a huge item and some owners are using a addendum for treating them, regardless it's hard to prove how they were introduced and harder to control if tenants hesitate to call for pest control treatment because they don't have the money to call for service, then you have potential for contamination to more units and it just spreads. 

I would also obtain a phase 1 environmental test performed to ensure grounds aren't contaminated, if they are - run!

So even elements that don’t appear damaged can be contaminated.

This includes assessments for issues such as lead-based paint, asbestos, mold, or soil contamination.

If you get a phase one and later the sight is contaminated you can often deploy the (innocent landowners defense).

Whiting is one of those areas that you need to be a bit careful though, Them and more so East Chicago have had a lot of incidents of lead and arsenic pollution in the soil.https://wgntv.com/2018/05/08/more-lead-contamination-found-in-nw-indiana-soil/

Fire damage--remove and replace; smoke damage--clean and deodorize (keep in mind that pretty much everything in the same airspace will have some measure of smoke contamination--this even includes the HVAC ductwork) ; water damage--mitigate and dry out (but if its remained wet for a period of time you might be looking at mold--remove and replace).

And, that's assuming that it is properly zoned, there's no contamination from a prior use, and if it's even a buildable lot. 

No, Jenni and Joe, I meant PEX.First, PEX, as several web sites have pointed out: More susceptible to contamination.

Hi everyone, I have a condo under contract that just tested positive for meth. 8.3 over 3 samples, so relatively low contamination.