Any financing document authorized by this chapter shall:
Any financing document may contain any other provision deemed necessary or desirable by the authority, including without limitation, in the case of the lease of a project by the municipality to a user, renewal or purchase options but any purchase option shall provide at a minimum for payment sufficient to reimburse the authority for all its current expenses incurred in connection with the project and to pay in full all bonds and other obligations of the authority together with interest thereon issued or incurred in connection with the project and unpaid at the time such option is exercised together with premiums, if any, payable in the event such bonds are called for redemption at the earliest practicable date. Any such purchase option may provide for payment of no additional consideration if all such expenses, bonds, or other obligations and interest have been paid in full when such option is exercised.
Any amounts paid by a user under any renewal or purchase option in excess of that necessary to pay such expenses, bonds or other obligations and interest shall be paid over on receipt by the authority, or directly, if the existence of the authority has terminated, to or for the account of the municipality which established the authority. If the authority is a consolidated authority, such payments shall be divided among the municipalities establishing such consolidated authority in such proportions as they may from time to time agree or, in the absence of agreement, in proportion to the average assessed value of the leased property for the three years next preceding the acquisition thereof by the constituent municipalities acting by and through the consolidated authority.
Mass. Gen. Laws ch. 40D, § 8