In addition to any other fees and expenses set forth in this chapter, in the event that the approving agency deems it necessary to hire consultants for technical review of an application, the applicant shall be required to bear the actual expense thereof, including, without limitations, any on-site inspections deemed necessary by such agency. The approving agency may require that the applicant fund an escrow account to be held by the City, in a reasonable amount to be determined by the approving agency, from which such expenses will be paid as they accrue. Thereafter, the approving agency may require that the applicant deposit additional sums into the escrow account to cover sums withdrawn therefrom to pay such expenses. Upon completion of review of the application and payment of all consultant fees, any sums remaining in the escrow account shall be refunded to the applicant.