Button "P" shows bed/room prices for each bed/room. The corresponding article is set via the menu "Reference data / Rooms", tab "Detail 2" field "Rack Rate". Additionally a price per day can be shown in the header for example for group rates. Menu item "Settings / Field Validation", field "harticle" default value. You might want to increase the header height: Menu item "Settings / Field Validation", field "header" default value.