Upon completion of demolition the inspecting official shall report to the city council the actual cost of demolition, grading, extermination, serving of notices, plus twenty percent of the total of said amounts to compensate for the cost of supervision and administration by the city. The city council may then proceed to assess said costs against the property pursuant to the provisions of Section 364.12 of the code of the state of Iowa.  (Ord. 84/T-3098).