HUD Inspection Reform and Capital Improvement Act of 2021 This bill authorizes the Department of Housing and Urban Development (HUD) to remove or reduce the pay of certain HUD employees for misconduct or performance. The bill also requires an entity receiving housing assistance payments for a dwelling unit to ensure that the unit is maintained to safe and sanitary conditions and authorizes HUD to take enforcement actions for failure to meet certain maintenance standards. Additionally, the bill provides for rental adjustments for certain properties receiving project-based rental assistance. Finally, the bill sets forth scoring and inspection frequency guidelines for properties receiving project-based rental assistance.