N.Y.C. Admin. Code § 27-119: § 27-119 Alteration cost: building value.

For the purpose of applying the foregoing provisions of this article, the cost of making alterations shall be determined by adding the estimated cost of making the proposed alterations computed as of the time of submitting the permit application, to the actual cost of any and all alterations made in the preceding twelve-month period; and the value of the building shall be determined at the option of the applicant on the basis of one and one-quarter times the current assessed valuation of the building, as adjusted by the current state equalization rate, or on the basis of the current replacement cost of the building, provided that satisfactory evidence of current replacement cost is submitted to the commissioner.