(a) A payment or performance bond is not required and may not provide coverage for the design portion of the design-build contract with the design-build firm under this subchapter.
(b) If a fixed contract amount or guaranteed maximum price has not been determined at the time the design-build contract is awarded, the penal sums of the performance and payment bonds delivered to the governmental entity must each be in an amount equal to the construction budget, as specified in the design criteria package.

(c) The design-build firm shall deliver the bonds not later than the 10th day after the date the design-build firm executes the contract unless the design-build firm furnishes a bid bond or other financial security acceptable to the governmental entity to ensure that the design-build firm will furnish the required performance and payment bonds before construction begins.