Section 7A. The board shall establish by rule an alternative procedure, hereinafter referred to as the informal procedure, for the determination of petitions for abatement of any tax upon real estate or tangible personal property, where such procedure is elected by both parties, except as hereinafter provided. Such procedure, to the extent that the board may consider practicable, shall eliminate formal rules of pleading, practice and evidence, and, except for the entry fee herein provided, may eliminate any or all fees and costs, or may provide that costs shall be in the discretion of the board.

An appellant desiring to be heard under the informal procedure shall pay to the clerk the entry fee provided in section 7, except as otherwise herein provided, and shall file: a written waiver of the right to appeal to the appeals court or the supreme judicial court, except upon questions of law raised by the pleadings or by an agreed statement of facts or shown by the report of the board; an election of the informal procedure; a written statement of the facts in the case; and the amount claimed in abatement, together with such additional information as the clerk may require, hereinafter collectively referred to as the pleadings. The minimum entry fee shall be determined annually by the commissioner of administration under the provision of section 3B of chapter 7 if the assessed fair cash valuation of the property on which the tax appealed from was assessed does not exceed $20,000 and such property is occupied in whole or in part by the appellant as his dwelling, contains no more than three units designed for dwelling purposes and is in no part used for any other purposes, or if the assessed valuation of the property on which the tax appealed from was assessed does not exceed $5,000 and such property is within the class of tangible personal property described in clause Twentieth of section 5 of chapter 59.

The pleadings may be made on forms to be supplied by the board and, if the appellant so requests and the assessed fair cash valuation of the property concerned does not exceed $20,000, shall be made out for the appellant by the clerk or an employee of the board designated by the board. The clerk shall then serve a copy of such pleadings upon the appellee. No further pleadings shall be required under this procedure if the appellee intends to offer no other defense than that the property was not overvalued or that the property was not improperly classified; otherwise, it shall file with the board within 30 days of the service of such pleadings an answer similar to that required under the procedure provided by section 7, hereinafter referred to as the formal procedure.

If the assessed fair cash valuation of the property concerned exceeds $20,000, the appellee, within 30 days of the date of service of such pleadings, may elect to have the appeal heard under the formal procedure by so notifying the clerk in writing and by paying him a transfer fee to be determined annually by the commissioner of administration under the provision of section 3B of chapter 7, in which case the said statement shall be considered to be a petition and such service to be service of the petition and the waiver of the right of appeal by the appellant shall be void. If the appellee does not so transfer the case, the informal procedure shall be deemed to have been accepted and all right of appeal waived by the appellee, except upon questions of law raised by the pleadings or by an agreed statement of facts or shown by the report of the board.

No statement under the informal procedure shall relate to an assessment on more than one parcel of real estate, except where the board shall specifically permit otherwise. The chairman shall provide for the speedy hearing of all appeals to be heard under the informal procedure. The chairman shall make every effort to reduce the expense of hearing cases filed under the informal procedure by directing whenever possible that petitions for abatement of taxes assessed upon real estate situated in the same general locality of the same town be heard together, irrespective of the identity of the appellants.