# How does HBook update availability? If someone books a room, will it be shown as unavailable?

HBook booking system is quite flexible and can be set to handle different situations:

- availability can be updated automatically when someone makes a reservation
- availability can be updated automatically only when you confirm a reservation from the back-end

**By default, HBook will immediately update availability.**

When you set accommodation types, you indicate how many accommodations of a certain type you have: for example, I create an accommodation type “Double Room” and I set that I have 5 of this type. It means that you have 5 Double Rooms. If someone books a double room for next Saturday night, then there will be now 4 Double Rooms left. And so on, until none is left for a date, which means that it can not be booked at this date.

**HBook allows you to change this default behavior.**  
If you prefer to block the accommodation **only when you confirm the reservation**, you will set in **HBook > Misc > Confirmation settings** that the reservation has to be confirmed before dates are blocked out in the calendar. You can set this differently for unpaid reservation or paid reservation. Typically, you may wish to set that dates are automatically blocked if there has been a payment but that it requires confirmation if there has been no payments (for example, if you ask for a bank transfer).