Any rebates, refunds, coupons, merit points, gratuities or any article of value tendered or received by any agency or governing authority from any vendor of material, supplies, equipment or other articles shall inure to the benefit of the agency or governing authority making the purchase. The agency or governing authority may, in accordance with its best interest, either take delivery of the article of value tendered and use the same or convert it to cash by selling it for its fair and reasonable value, making use of the proceeds from such sale for the exclusive benefit of the agency or governing authority.