N.J. Stat. § 54:4-112: Conditions precedent to compromise settlement

No such compromise settlement or adjustment shall be made unless the governing body shall be satisfied either that the property to be conveyed could not readily be sold at a price sufficient to pay and satisfy the amount of such municipal charges or that said municipal charges are illegal in whole or in part, or unless the proceedings taken to levy or enforce the same are at variance with the laws of this state in such case made and provided.