You should place a room Out of order to block it from use, and to remove it from your availability.
What's the difference between "Out of order" and "Out of service"?
Out of order rooms can't be used at all (for example, if the room floods). If a room is placed out of order, it is taken into account when calculating your availability.
Out of service rooms need some maintenance (for example, if the bed cover is missing) but can still be used by guests. If a room is placed out of service, it isn't taken into account when calculating your availability.
How do OOO rooms affect availability?
When you put a room Out of order, Mews takes it into account when calculating your availability. If the End time is before 6pm, availability for that evening won't be affected, but if it ends after 6pm (even at 6:01), your availability will be reduced by 1 for the evening.
Learn more about the differences between spaces which are out of order, out of service, or blocked for house use.