Property Tax Dispute Firm

I'm sure I'm not the only one here they got their property appraisal and was like WTF? My husband and I got lucky when we bought here in Tomball, this was in 2007. However, our taxes have increased by almost 50% in 15 years. Does anyone have a suggestion for a dispute firm other than Bennecourt? I used to work for the County and a hard no there. Thanks.