In Tom Benson Chevrolet, Inc. v. Alvarado, 636 S.W.2d 815 (Tex. App.--San Antonio 1982, writ ref'd n.r.e.), the Court addressed the admissibility of evidence similar to that submitted by Mear in response to West Loop's motion for summary judgment. In Alvarado, a purchase agreement contained a different sales price for a car than the price set forth in the retail installment contract. Id. The Court held that the purchase agreement was admissible because Alvarado's suit was premised upon a deceptive trade practice. Id.