As soon as the building or repairing of any sidewalk or curb or the filling or grading of any parking shall be completed, the work shall be inspected by the city engineer, and if the work shall have been done in conformity with the ordinances of the city, and with the order or resolution ordering the same, and the agreement with the contractor, if one has been made, a certificate shall be issued to the overseer of streets or contractor, as the case may be, which shall state the number of feet of sidewalk or curb, line measurement, built or repaired by the said overseer of streets or contractor, and the number of yards of parking filled or graded by the said overseer of streets or contractor, the street or avenue where constructed, and a description of the lots and blocks in front of, abutting on, or adjacent to which said sidewalk or curb has been built or repaired, or such parking has been graded or filled, which are chargeable with the cost thereof, and the amount due for the said work from each particular lot fronting on, abutting or adjacent to the said work so performed; and there shall be added to such amount ten percent (10%) thereof as compensation to the city for the cost of inspection by the city engineer and the cost of service of notices and publication of the same, and the said ten percent (10%) shall be assessed as a part of the cost of doing the said work, as the assessment for the same may be collected. (1960 Code, Sec. 6-106)