The main problem was the quality of the (four!) rooms that were offered to us.
At first we got room 444, but since we had booked a room with a single king-size bed, whereas here there were only two single-person beds, we refused this room.
We then got room 245. As soon as we saw it we were shocked: apparently the rooms in the fourth floor had been (at least somewhat) renovated, whereas those in the second floor were not. The laundry was yellowish instead of white, so we did not trust it to be clean; probably the room had not been used for a long time.
So, then we were offered room 472, which was at the fourth floor again. Yet we had a long list of complaints about this room too, so that we were indeed offered a fourth room. That, however, was mainly larger, but it lacked a balcony (present in room 472) and it was stinking. Besides, we were tired of packing and unpacking our bags once more.
Therefore, we agreed with the manager that we would stay in room 472, but that one would try to improve that room as good as possible: The light in the entrance was repaired, the missing chair was added, the broke chair on the balcony was replaced, the carpet was cleaned, etc.