Baltzar is equipped very well and has a quirky feel with its sloping, sometimes-creaking floors. It worked well for our group of 5 (3 adults, 1 teen and 1 child) although the living room was quite crowded when the sofa bed was folded out. I would recommend that guests using the sofa bed in the middle of summer bring sleeping masks because it stays light all night outside and the blinds in the living area do not block much of the light. The blinds in the two bedroom areas were much more effective at blocking the light. We only heard street noise one morning, when someone was pressure-cleaning a nearby building. Otherwise the apartment was fairly quiet even with the windows open. We already knew to expect 4 flights of stairs so this was OK. There was a key mix-up on our arrival but we called the support number that was provided with our booking and it was all resolved fairly quickly. We were also given a bottle of wine as compensation which we certainly weren't expecting! My only regret was that we couldn't stay longer.