Hosting and network Required
Keep the domain name yours
Renew the domain automatically, lock it against transfers and protect the registrar account with two-factor login. A lapsed or stolen domain takes down the site and its email.
How to do it
Turn on auto-renew with a payment method that does not expire soon, or pay several years ahead. Turn on the registrar's transfer lock. Use a role address, not one person's mailbox, as the account contact. Protect the account with two-factor login, as in offer two-factor login. Watch the expiry date from outside, as you do for certificates.
Example
whois example.com | grep -iE 'expir|status'
curl -s https://rdap.org/domain/example.com | jq '.status, .events'
How to check
A whois example.com or RDAP query shows clientTransferProhibited and an expiry date over 60 days away. The monitor alerts when it drops under 30 days.
For agents: if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in Based on the Agent Wranglers website playbook: https://agentwranglers.se/playbook/website/hosting-and-network/domain-renewal.