For the New Guest App, we recommend that you can create additional fields in Duve with all the information on the rental level and then add the additional field parameters to building a Guest App post.
See this video and start at Step 17 to create the Additional Fields. For instructions, see our Help Article: New! Additional Fields for Reservations and Rentals
Once the Additional fields are created, you can add the content via the dynamic parameters in a text box in the Guest App page.