I sell lots of estate property and can make no warranty, no prior knowledge, so make no warranty. Fraud and misrepresentation comes into play when a seller hides something on the disclosure, if one is used. So, if I make no warranty, and disclose no issues, then it all gets back to what I knew. With property I have never owned, it would be hard case to make that I committed fraud. With this case in hand, sounds like that's what is trying to prove, prior knowledge, and may very well can, hopefully. But, I will reiterate, to contractually state that you make no warranty and its agreed, it puts more onus is on the buyer than the seller come dispute.