We stayed in the Zaza apartment for a long weekend, and absolutely loved it. The building is reminiscent of "old Berlin", and I loved that aspect, coupled with the beautifully modern apartment. Check-in was smooth and quick, and Björn was a great host. This apartment also offers "best of both worlds" in that it is incredibly quiet at night, as it is set back from the main street, however outside the building complex door is direct access to restaurants, bars and unique shopping. The U2 is a 2 minute walk from the apartment, and 2 tram lines also run nearby for easy access to all the usual sights. I would definitely recommend this apartment for anyone wanting a "off the beaten path", but still central Berlin vacation.