In City of Houston v. Harris County Outdoor Adver. Ass'n, 879 S.W.2d 322 (Tex. App.-Houston 14th Dist. 1994, writ denied), appellees brought suit alleging that the city violated their constitutional rights by charging excessive operating permit fees. 879 S.W.2d at 325. The issue was whether the fees for off-premises operating permits were an impermissible occupation tax rather than a valid license fee. Id. There, the court upheld the trial court's findings that the fees were excessive and in the nature of an unlawful occupation tax. The court also found there was no way to challenge it. Id. at 333-34.