Kilz oil-based primer sprayed throughout and cleaning helps, but the odor still lingers for at least a year.  

@Ricky StaffordCould be minor--repair the walls, spray paint the house, slap down some new floor covering and repair the siding and it might be good to go if the plumbing and electrical are working.  

If you completely screw up and you end up with water spraying everywhere you can always hire a plumber.

@Jarred TateBecause this is a duplex I believe the numbers work for you. 

And keep spraying it with commercial grade round up .

I wouldn't have noticed it if they hadn't of tried to touch it up with white spray paint and got over spray on the beige siding.  

Even if they never sue, having the possibility of prospective tenants hear them rant about it doesn't reflect well.I had a tenant that had no problems voicing his "opinions", even when I had the pest control guy there spraying.

There is a theory that planting mint all around the foundation repels bugs.I just bought a building that had been sprayed monthly for a while and one of the first floor units still had a lot of cockroaches.

Because the remediation wasn't what they would do today (spray over the soot, etc.), the contractor was worried that the other repairs may not have been complete.It sounds like at some point I'll have to make a calculated decision.

I am working with my local LineX dealer to see if you can spray truck bed lining on it.