N.H. Rev. Stat. § 21-J:11

I. (a) Every person, firm, or corporation intending to engage in the business of making appraisals on behalf of a municipality for tax assessment purposes in this state shall notify the commissioner of that intent in writing. No person, firm, or corporation engaged in the business of making appraisals of taxable property for municipalities and taxing districts shall: (1) Enter into any contract or agreement with any town, city, or governmental division without first submitting a copy of the contract or agreement to the commissioner along with the names and qualifications of all personnel to be employed under the contract or agreement for review of the proposed contract or agreement and written recommendations of the department to be made to the municipality within 10 working days of receipt by the department; (2) Begin any appraisal work without first submitting a copy of the executed contract or agreement to the commissioner along with the names and qualifications of all personnel to be employed under the contract or agreement. (b) Any contract or agreement entered into for a reassessment or new assessment ordered by the board of tax and land appeals, pursuant to RSA 71-B, shall be first submitted to the commissioner for examination and approval. (c) This paragraph shall not apply to municipal employees. II. The commissioner, at no expense to the municipality, shall monitor appraisals of property and supervise appraisers as follows: (a) Assure that appraisals comply with all applicable statutes and rules; (b) Assure that appraisers are complying with the terms of the appraisal contract or agreement; (c) Review the accuracy of appraisals by inspection, evaluation, and testing, in whole or in part, of data collected by the appraisers; and (d) Report to the governing body on the progress and quality of the municipality's appraisal process. III. The commissioner shall adopt rules under RSA 541-A relative to the: (a) Contract or agreement provisions for a full revaluation, a cyclical revaluation, a partial revaluation, or a statistical update; and (b) Methodology for inspection, evaluation, and testing of data for the purpose of appraisal monitoring.