Purchasing and Procurement - As introduced, authorizes a local governmental entity with centralized purchasing authority to increase the threshold, from $25,000 to $50,000, over which public advertisement and sealed competitive bids are required; reduces the number of purchase orders, from three to two, that must be retained by a county after a purchase order or contract is issued or executed. - Amends TCA Section 5-14-111 and Section 12-3-1212.