We build on authoritative open data across housing finance: HMDA (mortgage applications and originations), agency loan-level disclosures (Fannie Mae, Freddie Mac, and Ginnie Mae), HUD FHA loan-level data, demographics microdata (ACS PUMS, CPS PUMS, ASEC), NMLS mortgage loan officer data, and FEMA National Risk Indicator (NRI) hazard risk data.