Cal. Gov. Code § 53569
Before selling any refunding bonds subject to the provisions of this article, any local agency shall advertise such bonds for sale at public sale and shall invite sealed bids therefor by publication of a notice once at least 10 days before the date of such public sale in a newspaper of general circulation circulated within the boundaries of each local agency to be aided by the public project to be financed by the issuance of such bonds; provided that, if an issue of bonds is less than five hundred thousand dollars ($500,000), a local agency is not required to advertise such bonds for public sale or to accept bids thereon pursuant to this section. If one or more satisfactory bids are received pursuant to such notice, such bonds shall be awarded to the highest responsible bidder. If no bids are received or if the local agency determines that the bids received are not satisfactory as to price or responsibility of the bidders, the local agency may reject all bids received, if any, and either readvertise or sell such bonds at private sale.
Ca. Gov. Code § 53569