Your CRM is losing accuracy at 2 percent per month — that is nearly a quarter of your contacts gone stale within a year. This guide shows you how to build a continuous, automated data hygiene workflow using ZeroBounce or NeverBounce, n8n, and your CRM’s native triggers. Includes a head-to-head verification tool comparison, SDR cost calculator, GDPR compliance checklist, and step-by-step n8n setup — no developer required.