The Planning Director may require any person, firm, or corporation to retain an expert consultant or consultants to study and report as to the compliance or noncompliance with the performance standards and to advise how an existing or proposed use can be brought into compliance with the performance standards. Such consultant shall be full qualified to give the required information and shall be persons or firms mutually agreeable to the City and to the owner or occupant of the use in question. The cost of such consulting services shall be borne by the owner or occupant of such property.