In 'Units & Rates>BAR Management' click 'Advanced' to access the additional options.
The options are:
Direct rates: Override BAR rate and set a specific price for a room category and date interval.
Unit types: Blocks out certain types of units from online booking and external channels. Used mostly to switch between house-room-bed mode.
Stay length: set minimum and/or maximum length of stay.
Availability: Set the maximum number of rooms that is districuted to channels and the threshold for when room categories should be sold out in channels.
Restriction: closeToArrival option will not allow arrivals on the selected day, closeToDeparture will not allow departure on the selected day and closeOut will not allow stay on the selected day.
Pick up length: The rooms will only be available in the selected interval, e.g if min is set to 1 and max to 3 the rooms will only be available 3-1 days before the selected day.
Stay unit: set weekly rental, default value for week is Sunday-Sunday.
Rateable period: used primarily for units booked hourly, the number will decide the price based on a minimum block of time. For example if rateable period is 4 the user will be charged for 4 hours if he book 4 or less hours, then for 8h if he books more then 4 h but not more then 8h.
Unit Availability: to block out units from booking.
If you use a channel manager please check if the rate options you use are supported by the channels and channel managers.