Subject to the limitations of this section, any type of contract which will promote the best interests of the state may be used; except that the use of a cost-plus-a-percentage-of-cost contract is prohibited. A contingency-based contract may be used only upon approval by the governor's office of state planning and budgeting pursuant to section 24-17-204. A cost-reimbursement contract may be used only when a determination is made in writing that such contract is likely to be less costly to the state than any other type of contract or that it is impracticable to obtain the supplies, services, or construction required unless the cost-reimbursement contract is used.