If you need to replace an aircraft, your options are -
(a) Negotiating and conducting an exchange transaction directly with an aircraft provider and obtaining credit toward the purchase of a replacement aircraft, following the procurement rules applicable to your agency; or
(b) Selling the aircraft and using the proceeds to offset the cost of purchasing a replacement aircraft, following 41 CFR part 102-39. Sales Centers (SC) that are currently authorized to conduct sales, as well as contact information for the GovSales Program Manager, are available on the GovSales Web site at http://www.gsa.gov/portal/content/105020.