When picking up the (digital) key, an amount of €10 must be paid. If you do not return the key, you pay for it with this deposit.
More guests in the same room can get more keys if needed.
In reality, the local people don’t lock their rooms at all.
We change the door locks at the last renovation. The main reason was that guests were taking the room keys with them, and we lived too far away from the city of Jesenice, where we could duplicate the keys. We solve that problem with digital locks.