The studio is in a great location in Berlin: very, very close to the center of things to see, such as museum island, but also near a couple good grocery stores and a street full of restaurants. A few minutes walk to a subway stop. The apartment is clean, with a large and complete kitchen and bathroom, and is pretty spacious for a studio. The downside in the summer is that, since one wall is entirely windows, it gets very hot on sunny days. Also, there wasn't any storage space, such as a dresser or hangers, where we could put our things, so we had to use tabletops or the floor.
Still, it's a great place in an excellent location, and Boris is really on top of answering questions, and provided us with a detailed guide to using everything in the studio (like the washing machine-- in Europe that can sometimes be tricky).