Section 218B(1) in The Mumbai Municipal Corporation Act, 1888
(1)If any party to an appeal against a rateable value under section 217 makes an application to the Chief Judge of the Small Cause Court either before the hearing of the appeal or at any time during the hearing of the appeal, but before evidence as to value has been adduced, to direct a valuation of any premises in relation to which the appeal is made, the Chief Judge may, in his discretion, appoint a competent person to make the valuation and any person so appointed shall, have power to enter on, survey and value the premises in respect of which the direction is given:Provided that, except when the application is made by the Commissioner no such direction shall be made by the Chief Judge unless the applicant gives such security as the Chief Judge thinks proper for the payment of the costs of valuation under this sub-section.