The performance guarantee shall be 120% of the performance guarantee estimate, and as surety, a performance bond, in which the owner shall be principal, shall be provided by an acceptable surety company licensed to do business in the State of New Jersey, or in lieu of the bond, cash or a certified check shall be deposited with the Township by payment to the Township Treasurer. The Township Treasurer shall issue a receipt for such cash deposits and shall cause such cash to be deposited in a bank named by the Township, in the name of the Township, to be retained as security for completion of all requirements and to be returned to the owner on completion of all required work and expiration of the period of maintenance guarantee, or in the event of default on the part of the owner, to be used by the Township to pay the cost and expense of obtaining completion of all requirements. Every bond, whether cash or surety, shall contain a clause to the effect that a determination by the Township Engineer that the principal has defaulted in the performance of his obligation shall be binding and conclusive upon the surety and the principal. A performance guarantee shall be valid for a period of two years upon acceptance by the Township. If improvements or significant percentage of improvements have not been completed at this time, the performance guarantee will be renegotiated with the applicant and revised accordingly with one-year extension periods.