128. The council of a regional county municipality may, by by-law, for the purposes of an agreement under section 123 and in respect of a local municipality whose territory is not covered by the agreement or only a part of whose territory is covered by the agreement, prescribe criteria for the determination of the number of votes and the number of the population attributed to any representative of the local municipality for the purpose of decision making by the regional county municipality in relation to the carrying out of the agreement. The by-law may also establish criteria for the determination of the proportion of the local municipality’s contribution to the payment of the expenses of the regional county municipality relating to the agreement.