What you need to do is look for a "for sale" button on the browse screen, according to Redbox's Help Center. If there are items for sale, clicking that button will bring them up. If there is no "for sale" button, then there are no items for sale from that kiosk. If you are signed up to receive Redbox emails, and have rented games or movies from them, they may target you with an email alerting you when there are items for sale.
Have you ever purchased an item from a Redbox kiosk?
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