Before we talk about how to reactivate, it's worth understanding what's realistically in a typical agency's old lead database, because not all cold leads are the same.
The #1 mistake real estate agencies make after getting leads is assuming their team will handle follow-up consistently enough to convert leads at scale.
The agent who replies in under two minutes usually wins the viewing. Everyone else gets ignored, blocked, or politely told "I've already booked with someone else."
The fastest agency does not always have the best property. It has the best system.