I'm a graduate student who comes to Berlin from time to time to do research. I rented an apartment in Prenzlauer Berg for a month and was extremely happy with the location and with the apartment and service overall. The apartment is right near the M1 tram line, which takes you directly to Mitte, the HU, Unter den Linden, and lots of other great places. And it's also on the U2 line, which gets you to Potsdamer Platz, the Stabi, and everywhere else. For going out, though, I often just stayed in the area. Prenzlauer Berg is full of restaurants, clubs, cafes, and bars that were within walking distance of the apartment. The place was clean and completely stocked with everything I needed for my extended stay. It felt nice having such a comfortable place to come back to at the end of the day, and really started to feel like home by the end of the month. The owner was very welcoming and willing to answer a lot of questions I had about the area, places to go, transportation, etc. I'd recommend the apartment to anyone who has work to do in Berlin, but also anyone who just wants to come and have a good time in the city.