Prior to the granting of approval of the final plat the subdivider shall have installed the required improvements, or shall have furnished a performance bond, certified check or letter of credit to the Village for the amount of the estimated construction cost of the installation of the improvements as approved by the Village Engineer. Before the bond, certified check or letter of credit is accepted, it shall be approved by the Village Council and their legal counsel. The term of the bond, certified check or letter of credit shall extend twelve months beyond the completion date of the project unless released prior thereto by the Village Council. A completion date shall be established by the subdivider and approved by the appropriate officials. The completion date shall be stated in the bond, certified check or letter of credit. The period of time stipulated shall not exceed two years from the date of the final plat approval unless an extension is requested in writing by the subdivider and granted in writing by the Village Council.