(a) Municipal boards of improvement shall have control of the construction of the improvements in their improvement districts.
(b) The boards may advertise for proposals for doing any work by contract and may accept or reject any proposals.
(c) All contractors shall be required to give bond for the faithful performance of such contracts as may be awarded them, with good and sufficient securities, in double the amount of the contract work, and the board shall not remit or excuse the penalty or forfeiture of the bond for the breaches thereof.
(d) The boards may appoint all necessary agents for carrying on the work and may fix their pay.
(e) The boards may buy all necessary material and may sell any such materials or implements as may be on hand, and which may not be necessary for the completion of the improvement under way, or which may have been completed.
(f) The boards may, in general, make all contracts in the prosecution of the work as may best subserve the public interest.