Franz Airbnb was very nice! It is very close to the U-Bahn Station Karl Max U7 (a 5 min walk) from where you can access every corner of Berlin and even closer to the Bus Station Geygerstr at Sonnenallee (2 min). The room itself was very clean and big and the bed was comfortable as well.
Franz's mother was very very nice! She showed us the room and bathroom and was very helpful whenever we had questions. Would recommend!