Let me begin with Anderson and Guido - two wonderful hosts. They were so friendly and made me feel right at home. Communication was always very fast and clear. They also gave me plenty of suggestions for things to do, including one of my favorite restaurants of the entire trip.
The apartment itself is also great. The bedroom was fully equipped with everything one or two people would need, and had access to a balcony. The balcony was great and would be beautiful in the summer time. You also have a private bathroom as well as a shared fully equipped kitchen (With snacks, delicious coffee, eat, etc!) and living room. The space was very nice with lots of natural light.
The appartment location is great. There is a subway station right outside the apartment (the train passes nearby but is not loud and never bothered me). There is also two other train lines within a 10 minute walk. Transit was extremely easy and convenient from this apartment to all parts of the city. There is also plenty of great restaurants and bars nearby.
Overall I would 100% stay here again. It made my experience in Berlin much better than I could have imagined.