You don't pay for self-custody, but for cloud hosting. If you host yourself, it's completely free

It costs 21k sats / month, but it's10k sats for first 3 months

Subscription payment is built on nostr:npub19hg5pj5qmd3teumh6ld7drfz49d65sw3n3d5jud8sgz27avkq5dqm7yv9p - it allows us to charge subscription amount from the wallet. You can technically stop it but then we will close your cloud deployment after some time