A contract modification, change order, or contract price adjustment under a construction contract in excess of an amount established by regulation of the commissioner is subject to prior written certification by the fiscal officer of the agency responsible for funding the project or the contract, or other official responsible for monitoring and reporting upon the status of the costs of the total project budget or contract budget, as to the effect of the contract modification, change order, or adjustment in contract price on the total project budget or the total contract budget. If the certification of the fiscal officer or other responsible official discloses a resulting increase in the total project budget or the total contract budget, the procurement officer may not approve the contract modification, change order, or adjustment in contract price unless sufficient funds are available, or the scope of the project or contract is adjusted to permit the degree of completion that is feasible within the total project budget or total contract budget as it existed before the contract modification, change order, or adjustment in contract price under consideration. A contract modification, change order, or adjustment in contract that is signed by both parties and has been reasonably relied on by a contractor is presumed to be valid even if the provisions of this section have not been met.