Prior to filing of the final map with the city council; the subdivider shall file security in the amount equal to the estimated cost of the public improvements, as determined by the city engineer; and additional security for labor and materials in an amount not less than fifty percent of the estimated cost of the public improvements. Security may be furnished in any form permitted by Section 66499 of the Government Code; provided the same is approved in form and as to amount by the city attorney and city manager; respectively; and provided that the city attorney approves the kind and amount of cash deposit or certificate of deposit (other than surety bonds) submitted in each case. As a condition precedent to approval of improvement security; other than security bonds; the subdivider shall be required to submit on demand such proof of value of the security offered; such as appraisals; title guarantees; etc.; as will be necessary to establish that the public improvements are fully secured. Any surety bonds submitted as security shall be issued by a surety company authorized to transact a surety business in California. (Ord. 1379 NCS §1, 1979; Ord. 1296 NCS §3, 1978; Ord. 1046 NCS §1 (part), 1972; prior code §22.6.501.)