In all cases where work or material shall for any purpose be by any person furnished to or for the City, the person so furnishing such work or material, or both, shall be required to make out a detailed account of the items of such labor or material, or both, as the case may be, with the charge of each item set opposite the same. However, in all estimates on contracts for special improvements except final estimates, it shall be sufficient, unless the Director of Finance shall otherwise require, for the Commissioner of Engineering and Construction to certify to a statement showing the total value of the work or material furnished, the amount of all estimates previously given thereon, the percentage retained and the balance due the contractor.