Can visitors choose their own payment method? If they select online payment but don't complete the payment, does the order still exist?

Payment methods are configured by the seller in Trading Condition Setting. Visitors cannot choose—a public page has only the one payment method set: PayPal, PAYUNi, or offline payment (which doesn't require an online payment mechanism). Online payment also follows a "create order first, then pay" flow: the moment the visitor clicks submit, the PI is already created, and they are then directed to the payment page. If the visitor doesn't complete payment, the order remains on record. The seller will see an unpaid PI. The visitor can click "Go to payment" in the results window, or click "Skip, pay later". Once the payment page opens, the original window counts down 5 minutes and checks the payment status every 3 seconds. The countdown is just a reminder—the order won't be cancelled when time runs out. If the screen hasn't changed after payment, click "Refresh payment status". For offline payment orders, checkout first displays a reminder: "Shipping will be arranged only after the seller receives the payment".