If you have a property that you were renting out by room but decide to rent it out entirely, here's what you need to do:
In the first editable field - Content - you need to check "Entirely" in the Booking Type section.
This will bring back the Pricing and Availability sections in the main menu, from the Rooms Manager.
Both sections will need to be re-filled.
Additionally, the amenities will need to be re-checked in the Attributes section.