The building is unfortunately very outdated; pretty much the only ventilation in the room was in the toilet/bathroom which worked only when the motion activated lights were on. We also noticed black mold in the ceiling corner of our shower. Only ventilation option in the room was opening the windows and the noises from the street (frequent ambulances (expected from Berlin, of course), other quests who were partying and smoking outside etc.) disturbed our sleep. Since the building is fairly old, we didn’t expect perfection, however the horribly stained carpets and door frames that were basically falling apart were not a part of our expectations. Most of the reception staff were kind and very accommodating, however a few were very rude (this could be due the lack of air conditioning in the lobby as well, those poor workers were sweating). Breakfast was good enough, however I’d wish for more variety even on a weekly basis. We stayed for 8 nights and breakfast was identical every single day.