7-12-4147. Procedure for property owners to do improvement work. The owners of three-fourths of the frontage of lots and lands liable to be assessed or their agents, who shall make oath that they are such owners or agents, shall not be required to present sealed proposals or bids but may, within 3 days after the award pursuant to 7-12-4143, elect to take such work and enter into a written contract to do the whole work at a price at least 5% less than the price at which the same has been awarded. All work done under such contract shall be subject to the same plans and specifications governing the lowest responsible bidder.