Originally Posted by BruceyBonus

At a minimum, expect the following fees:
Airport Booking Fee €20.00
Airport Check In Fee €50.00

The website lets you book tickets for up to 2.5 hours ahead, so you could avoid these by booking online then using either the mobile app to check in or finding a printer. If you check in online, but cannot print the boarding pass, the re-issue fee is €15.00, which is obviously cheaper than the airport check-in fee.