In order to carry out the purposes provided in section 79-1204, educational service units may purchase, lease, or lease-purchase real estate, equipment, supplies, services, and personal property for their own use. Educational service units may, either individually or collectively, purchase, lease, lease-purchase, or act as purchase agent for administrative and instructional supplies, instructional equipment, instructional services, and personal property for resale only to educational entities. When an educational service unit advertises for bids for administrative or instructional supplies, instructional equipment, instructional services, and personal property, acceptance of any bid submitted to the educational service unit shall obligate the educational service unit to award the contract in accordance with the plans and specifications and in the quantities set forth in the bid documents.