Area has been treated for surface discoloration? Mold?

[Michael Vitale]

Hey guys I was looking for some advice on a fix and flip. I'm very new to this. The property is 1400 sq ft with about a foot of water sitting on the floor in an unfinished concrete basement. There are signs posted in the house on same wall of all three floors saying "this area has been treated for surface discoloration, it has not undergone sub-surface inspection" it is even posted on a concrete wall in the basement. I know it has to do with mold I'm guessing from the sitting water, but why it would be upstairs is bothering me too. The interior ceilings look undamaged but I obviously can't see the top of the roof. What does this sign mean and has anyone had experience with these kind of deals. There is no contigincy allowed as it is bank owned. Can anyone explain what this might mean for me?