Whenever the governing body notifies in writing the owner of any building or structure theretofore rat-stopped as hereinabove defined, that there is evidence of rat infestation of the building or structure, the owner shall immediately institute appropriate measures for freeing the premises so occupied of all rats. Unless suitable measures for freeing the building or structure of rats are instituted within five days after the receipt of notice, and unless continually maintained in a satisfactory manner, the city is hereby authorized to free the building or structure of rats at the expense of the owner thereof and the City Clerk shall submit bills for the expense thereof to the owner of the building or structure and if the same are not paid, the City Clerk shall certify the amount due from the owner to the City Treasurer, and the owner shall be promptly billed therefor. The expense thereof shall include the cost of labor, materials, equipment and any other actual expense necessary for the eradication measures.