N.Y. RRD Law § 173-F

§ 173-f. Every terminable permit, and every amendment to any existing\nlicense, grant, franchise, permit or consent incorporating therein the\nterms of a terminable permit, shall contain an irrevocable option for\nthe purchase by the city, town or village, either directly or through\nits nominee or nominees, of all or any part of the property, plant and\nequipment of the street surface railroad at any time, at a price agreed\nupon or to be ascertained and determined in a manner agreed upon at the\ntime of the granting of the permit or amendment and to be set forth\ntherein. Any such permit or amendment may contain provisions for\namortizing out of earnings or in accordance with an amortization\nschedule or schedules to be set forth therein, over a period not\nexceeding fifty years, the price to be paid for all or such part of the\nproperty, plant and equipment of the street surface railroad and for any\nadditions thereto or betterments or improvements thereof, so that upon\nthe exercise of the option the city, town or village, or its nominee or\nnominees, shall be required to pay only the unamortized portion of such\nprice, and may contain any other terms, agreements, stipulations and\nconditions as may be authorized by any statute of the state, or as the\ncity, town or village may deem proper and in the public interest, and\nmay provide for the termination thereof for any legal cause.\n