This legislation directs the Comptroller General of the United States , also known as the Government Accountability Office (GAO), to undertake a comprehensive study. The primary objective of this study is to ascertain the total cost of construction materials that were procured for the United States-Mexico border wall but ultimately remained unused. The scope of the study specifically covers materials obtained during the period from January 20, 2021, to January 20, 2025 . Following its completion, the GAO is required to submit this detailed report to Congress within 90 days of the bill's enactment, providing an accounting of these specific expenditures.