Once approved, a permit for the erection, construction, or placement of a temporary sign may be renewed for an additional period of thirty (30) days. Only two such renewals are authorized. All renewal fees under this chapter shall be fixed and determined by the Council, adopted by resolution, and uniformly enforced. Such renewal fee may, from time to time, be amended by the Council by resolution. A copy of the resolution setting forth the current renewal fee shall be kept on file in the office of the City Administrator, and be open to inspection during regular business hours.