CHECK-OUTS
In Property Settings / Reservation settings you will find an option that puts restrictions on editing checked-out reservations.
When this option is enabled:
a) You cannot edit the reservation. The booking information will appear as inactive. Only the payment can be taken.
b) In order to edit the booking, you need to use the un-checkout option.
When you un-checkout a reservation or you delete it, a special system notification is sent. I can be set up in the Property settings / Notifications section.