You will get a custom code from the host 24h before checkin for the access to the building and inside door. The code lasts as long as your reservation and is deleted from the database afterwards. Please view this video for a more detailed guide on how to check-in.

For Early check-in or late check-out you have to contact the host directly. These options are deppendant on the avaliability of the rooms you rented after or before your check-in/out