A. Supplies, materials, equipment or contractual services, purchased from another unit of government at a price deemed below that obtainable from private dealers, including war surplus;

B. Contractual services purchased from a public utility at a price or rate determined by state or other government authority;

C. Supplies, materials, equipment or contractual services purchasable under the contract of another governmental agency in which contract the city is authorized to participate. [Ord. 14-27 § 4.]