N.Y. Comp. Codes R. & Regs. Tit. 9 §§ 270-6.6
In the event an applicant for a lease, easement or other interest in real property shall dispute and request a reduction of the commissioner's determination of the value of the interest to be conveyed, the commissioner shall, upon the applicant's submission of an appraisal of the value of such property interest conducted in accord with standard and accepted appraisal methodology by an independent appraiser qualified as prescribed in this section and which appraisal varies in its conclusion as to value by 10 percent or more or the value previously established by the commissioner, and upon the applicant's agreement to be bound thereby, contract with a second independent appraiser, qualified as prescribed in this section, to render an appraisal of the value of the interest proposed to be conveyed, the results of which appraisal shall be binding upon both the applicant and the Commissioner of General Services. Such appraiser shall be selected by the Commissioner of General Services from among a group of at least three appraisers identified by the applicant all of whom must be qualified as prescribed in this section and each of whom must agree to employ standard appraisal methodology. For the purposes of this provision a qualified appraiser shall be certified by the Secretary of State to transact business as a real estate general appraiser and shall conduct a regular business of the appraisal of real property interest. In the event that the appraisal contracted for in such manner shall conclude that the value of the property interest in question is equal to the value previously determined by the commissioner plus or minus 10 percent, the entire cost of such appraisal shall be borne by the applicant, otherwise, the entire cost thereof shall be borne by the Commissioner of General Services.
N.Y. Comp. Codes R. & Regs. Tit. 9 §§ 270-6.6