If you don't want to commit to an HBO Max subscription, you have the option to pay one-time fee to rent or buy "The Batman" from a video-on-demand (VOD) retailer. Amazon Prime Video, Vudu, and Google Play all carry "The Batman." It costs $25 to rent the movie and between $30 and $32 to buy it, depending on which service you choose. You typically get 30 days to start watching a movie once you rent it, and then 48 hours to complete it after you hit play.