Section 6 - Payment and lien of tax1.To the extent the tax imposed by section three of this part shall not have been previously paid pursuant to section eight of this part, (a) such tax, or the balance thereof, shall be payable to the commissioner of finance in full at the time the report is required to be filed, and(b) such tax, or the balance thereof, imposed on any taxpayer which ceases to do business in the city or to be subject to the tax imposed by this part shall be payable to the commissioner of finance at the time the report is required to be filed; all other taxes of any such taxpayer, which pursuant to the foregoing provisions of this section would otherwise be payable subsequent to the time such report is required to be filed, shall nevertheless be payable at such time. If the taxpayer, within the time prescribed by section five of this part, shall have applied for an automatic extension of time to file its annual report and shall have paid to the commissioner of finance on or before the date such application is filed an amount properly estimated as provided by said section, the only amount payable in addition to the tax shall be interest at the rate set by the commissioner of finance pursuant to section eighty-seven of part six, or, if no rate is set, at the rate of six per centum per annum upon the amount by which the tax, or the portion thereof payable on or before the date the report was required to be filed, exceeds the amount so paid. For purposes of the preceding sentence: (1) an amount so paid shall be deemed properly estimated if it is either (A) not less than ninety per centum of the tax as finally determined (computed without regard to any credit allowable under section four-a of this part), or (B) not less than the tax shown (computed without regard to any credit allowable under section four-a of this part) on the taxpayer's report for the preceding taxable year, if such preceding year was a taxable year of twelve months; and(2) the time when a report is required to be filed shall be determined without regard to any extension of time for filing such report.2.The director of finance may grant a reasonable extension of time for payment of any tax imposed by this part under such conditions as it deems just and proper. 3.Subdivision one of this section shall apply to a taxpayer which has a right to a credit pursuant to section four-a of this part, except that the tax, or balance thereof, payable to the director of finance in full pursuant to subdivision one of this section, at the time the report is required to be filed, shall be calculated and paid at such time as if the credit provided for in section four-a of this part were not allowed. N.Y. General City Model Law § 6