N.J. Stat. Ann. § 56:6-12

507. Every retail dealer shall keep such records as may be prescribed by orders, rules or regulations of the director and as may be necessary to the determination of whether or not such retail dealer has observed the provisions of this act. All such records shall be safely preserved for a period of four years in such manner as to insure their security and accessibility for inspection by the director or any employee of the Division of Taxation engaged in the administration of this act. The director may consent to the destruction of any such records at any time within said period.