Limit number of appointments
It is possible to set a limit for the number of appointments per day. This can be set separately for every appointment type. Go to Settings > Extra functionality, and tick 'Limit the amount of appointments for a specific appointment type' and click on save at the bottom.
Go to Manage > Services and click on 'Adjust' (little notepad and pen) at the appointment type you wish to set. Right under 'Minimum Time for Cancellation' now appears 'Maximum Number of Appointments per Day'. Here you enter the maximum number of appointments that can be executed per day for this appointment type and subsequently click on 'Create'.