The commissioners authorized by Section 57-1-131 shall be deemed to be the governing body of the municipality. Except as hereinafter provided, the term of each commissioner shall be four (4) years, and until his successor shall have been appointed in like manner and shall have qualified. In case of death, disability or resignation, the vacancy shall be filled for the unexpired term by appointment to be made by the board of supervisors of the county in which such vacancy occurred. Of the two (2) commissioners first appointed by each county, one (1) shall be designated to serve for a term of two (2) years, and the other shall be designated to serve for a term of four (4) years, and until their respective successors shall have been appointed and qualified. The aforesaid designations shall be made by the respective boards of supervisors. Such commissioners shall constitute a board, and shall organize by electing a president and a secretary, and by adopting an official seal with which to attest its official acts, and by adopting a name by which the municipality formed by the districts involved shall be known and recognized. The adoption of a name for any such municipality prior to the enactment of this statute is hereby validated and confirmed. The commissioners shall meet at such time and place as they may determine, shall keep full, complete and permanent minutes of their meetings and records of their proceedings, and shall receive no compensation for their services, except reimbursement for actual and necessary expenses incurred by them in traveling in performance of their duties. No action taken by such commissioners and no contract or agreement entered into by them shall be valid and effectual unless and until the same is approved by the board of supervisors of each county having territory involved, by resolution spread at large upon the minutes of such board.