I was frustrated as the key didn’t work. I kept telling the host that the key doesn’t work and a) they were slow in replaying and b) they kept telling me that I am doing it wrong!
Finally they left another key inside when I was gone and surprise it worked ! They let me in a day before via iPhone application.
Also at night there were weird noises in the building and there was somebody drank at night trying to open a door on my floor. Finally, I believe by accident someone bumped into front door from the flat and it was about 3 am.
A lot of stairs no lift but it was mentioned to be before.
Thanks, K.