Recently stayed in Alex's apartment and have to say it was great! Loved that the location was near shopping, sites, and the U-bahn (train station). The apartment has everything you want from the small but efficient kitchen to the spacious feel of the apartment. It's great for a couple or even up to 3 friends. The apartment has great upgrades and there are nearby grocery stores/markets. The KADEWE (department store) is a ten minute walk if you want to shop and the gay area is minutes east by foot. I truly enjoyed being able to hop on the train and get to the other great areas of berlin Potsdamplaz, Mitte, Kreuzberg, etc. Alex's friend, Michael, met me at the apartment and one day when the WiFi didn't work he came promptly to fix it. He also was very helpful with any questions I had. The ride from the airport was easiest by cap at 20 euro and no traffic. Can be done by train but the hassle is not worth it. Definitely recommend this and will use again if I return to Berlin.