Whenever any district is organized hereunder, there shall be included in the cost and expense thereof: (1) The cost of all of the construction or improvement authorized in the district, including that portion of the construction or improvement within the limits of any street or road intersection, space or spaces; (2) the estimated costs and expenses of all engineering and surveying necessary to be done by the county engineer or under his or her direction or by such other engineer as may be employed by the county commissioners; (3) the cost of all advertising, mailing, and publishing of all notices; (4) the cost of legal services and any other expenses incurred by the county for the district or in the formation thereof, or by the district in connection with such construction or improvement and in the financing thereof, including the issuance of any bonds.