My favourite of all the Airbnbs I've stayed in over several summers in Berlin. Location was excellent — around the corner from a big grocery (EDEKA), a brief walk to a convenient central train station (Ostkreuz — you can get the fast train to the airport, and the S-Bahn to elsewhere, from there), around the corner from a tram stop, and surrounded by many restaurants, in a lovely little spot in Friedrichshain.
The unit was exactly as advertised — so beautiful, with everything you could need, and such a joy to live in that I wish we could have stayed longer. The design is so good, I can't stress it enough. The lighting in particular is just fantastic, and the bedroom never gets too hot, even in the summer.
Unfortunately there is no lift, though it appears one is being built, which is great for future tenants, and the door lock's a little tricky at first (I panicked when I couldn't get it open the first time and texted Jennifer, haha), but you'll get the hang of it — just go gently.
Communication with Jennifer was so easy, and it was lovely to get to meet her for the key handoff. She was the most accommodating host, and so pleasant to chat to. Sending many thanks to her and to Simon, and hoping to book again next summer!