PostHog Cloud EU to Self-Hosted: Cost Math and 4 Gotchas I Hit

A user migrated from PostHog Cloud EU to a self-hosted solution on Hetzner to reduce costs from 180 EUR/month to 42 EUR/month, citing a cost crossover near 2M events/month. The migration, initially a "weekend project," took six days due to four key issues: a daily event cap, ClickHouse memory limits, reverse proxy persistence, and an outdated plugin.