Sec 23.01 Texas Property Tax Code
The market value of property shall be determined by the application of generally accepted appraisal methods and techniques. If the appraisal district determines that the appraised value of property using mass appraisal standards, the mass appraisal standards must comply with Uniform Standards of Professional Appraisal Practice. The same or similar methods and techniques shall be used in appraising the same or similar kinds of property. However, each property shall be appraised based upon the individual characteristics that affect the property’s market value, and all available evidence that is specific to the value of the property shall be considered in determining the property’s market value.