Mass. Gen. Laws ch. 112 § 193
Each state-certified general real estate appraiser, state-certified residential real estate appraiser or state-licensed real estate appraiser shall retain, for at least five years, originals or true copies of all written contracts engaging his services for real property appraisal work and all reports and supporting data assembled and formulated by the appraiser in preparing such reports.
This five year period for retention of records shall be applicable to each engagement of the services of the appraiser and shall commence upon the date of the submittal of the appraisal to the client unless, within such five year period, the appraiser is notified that the appraisal report is involved in litigation, in which event the five year period for the retention of records shall commence upon the date of the final disposition of such litigation.
All records required to be maintained under the provisions of this section shall be made available by the state-certified or state-licensed real estate appraiser for inspection and copying by the board on reasonable notice to the appraiser.
Mass. Gen. Laws ch. 112, § 193