there is a law every buyer need to be beware especially when he buys property, so you can club the buyer too, as he ailed in his duty to properly ascertain the nature o property sold by the other lady seems a living in type as it appears in the narration. so yes she has derauded, as such she alls under cheating sec 420 o ipc, breach o moral contract under contract Act, ater all all laws are some kind o social contract documents, however much legislature passes a statute but such statutes too vulnerable and can be tested on social norms and like parameters, so judicial review is born. There is no absolute sanctity o any law as such, in advance interpretation o laws and statutes please