I can't say if it's a frivolous suit, because I haven't read the actual complaint against the defendant.
Basically, you're complaining that you were induced into purchasing the property based upon a misrepresentation of the seller. This sort of suit is generally barred by a relatively short statute of limitation. However, that limitation may only begin from the date that you actually discover the misrepresentation.
In any case, I don't believe the lawsuit would be frivolous, because you have a "colorable" claim. Regardless, your original contract with the seller may have provided for attorney's fees in the event of a dispute, which would make it possible for the seller to obtain prevailing party fees, regardless of the character of the suit.
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