Paid tickets and self-service upgrades

Paid tiers sell through Stripe on your connected account (Turtini's fee is the standard app fee). A buyer picks a tier on the public page, pays via embedded checkout, and gets their QR + Add-to-Wallet pass.

Guests can also upgrade their own pass — no staff needed. From their pass (the "Upgrade my pass" link, or /flow/upgrade/:id) they see tier upgrades (GA→VIP) priced at just the difference, or, on a pay-what-you-can pass, top-ups to reach a giving level. They pay the delta and the new access lands on their existing QR / wallet card automatically.