Harrington’s rise to become CEO of FirstTeam Real Estate began with a star turn as the owner of Star Estates, the South Orange County-based firm she built into a 130-agent brokerage before merging it in 2018 with FirstTeam, Southern California's largest independent real estate brokerage. Following a stint as COO, she became CEO in 2023. In 2025, the New Jersey native and United States Marine Corps veteran continued to grow the business, expanding to Washington and Idaho as part of a national growth strategy. But with more than 1,800 agents boasting $6 billion in annual sales, expect more from Harrington in 2026.