Checkout keyCreates invoices and reads their state. This is the one your storefront uses.
Wallet keyIssues deposit addresses and reads customer balances. Never needed by a storefront.
Payout keyMoves money out. Held by your backend only, and subject to the destination allowlist.
Five keys per kind. A key is shown once, at creation — we store only a hash, so a lost key is rolled, never recovered.