When Pierce County elects to dispose of real property by sale, lease, or exchange, the County shall advertise to the extent which it deems necessary to effect an advantageous sale. The County may implement disposition of real property by public advertisement or private negotiation at its discretion, provided that disposition of real property with a value equal to or in excess of $25,000.00 shall be preceded by publication of a notice in the legal newspaper at least once each week for two consecutive weeks, the last notice to appear no more than seven days prior to the date of the closing of the disposition. An advertisement of sale of County property must particularly describe the property to be sold. When real property is to be sold, the advertisement of sale must contain both the street address, if available, and the legal description of the part and parcel.