Get the Lead Out of Assisted Housing Act of 2018 This bill addresses the removal of lead from drinking water in federally assisted housing. Specifically, the bill requires the Department of Housing and Urban Development (HUD) to require specified testing and remediation with respect to water service lines containing lead; authorizes HUD to inspect all sources of lead contamination in federally assisted housing and to mitigate sources of lead exposure; establishes a grant program for states and local governments to create inventories of water service lines containing lead and to test for lead in the drinking water at child care facilities, schools, and public water fountains; and allows recipients of certain HUD assistance to use such assistance to replace water fixtures and service lines containing lead.