N.J. Stat. § 40A:12-16
The governing body of any county, by resolution, or any municipality, by ordinances may exchange any lands or any rights or interests therein owned by the county or municipality, except lands used for public highways or places, for other lands or rights or interests therein desired for public use. The county or municipality may exact and receive a cash consideration in addition to such other lands or rights or interests therein when such exchange shall be authorized, and such governing body determines that the lands or rights or interests therein to be conveyed to such county or municipality or such lands or rights or interests therein and the cash consideration to be paid are at least of equal value to, and their acquisition is more advantageous to, the county or municipality for public use, than the lands or rights or interests therein to be conveyed by the county or municipality, and that it is in the public interest that such exchange of lands or rights or interests therein be consummated. Any prior dedication or determination for use for park purposes of such land or any part thereof, shall not preclude an exchange thereof or rights or interests therein under this section but where the lands or rights or interests therein to be exchanged by a municipality are lands or rights or interests therein that have been dedicated and determined for use for park purposes, or are rights or interests in lands so dedicated or determined, the lands or rights or interests therein received in exchange therefor by the municipality shall be used for the same purposes. For purposes of this section, any land or rights or interests therein to be exchanged by the county or municipality shall be valued at not less than the amount for which it was acquired or in the case of an acquisition by gift or devise, in an amount of not less than the "full and fair value" of the land or rights or interests therein as determined by the assessor of the municipality in which it is located pursuant to R.S. 54:4-23 for the tax year in which the land was acquired by the county or the municipality. Any land or rights or interests therein which shall be conveyed to the county or municipality in exchange for any county or municipal land or rights or interests therein shall be valued at no more than the "full and fair value" determined for the land or rights or interests therein by the assessor of the municipality in which the land or rights or interests therein is located pursuant to R.S. 54:4-23 for the then current tax year. In any case in which the value of the county or municipal land or rights or interests therein to be exchanged exceeds the value of the land or rights or interests therein to be received by the county or municipality, the county or municipality shall exact additional cash consideration, as authorized herein, equal to the difference of the two values as determined pursuant to this section.
N.J.S. § 40A:12-16