How storefront carts and checkout work

Each public storefront has its own cart. Adding an item from Storefront A does not mix it with Storefront B; you can have several open carts and check out each seller separately. This keeps the seller as the direct PayPal payee.

An item in a cart is not reserved. Before checkout, ThriftRunner verifies that it is still published, unsold, and still the same price. Checkout then creates a short reservation so two buyers cannot pay for the same item simultaneously. If someone else sold or reserved it first, the cart clearly identifies the conflict and blocks checkout.

Continue to PayPal only when the seller has an active connected account. PayPal handles approval and sends a signed completion event. Only verified completion marks the listing sold. ThriftRunner never holds the money.