I stayed in Eleni's apartment for 2.5 weeks as I had just moved to Berlin for a new job. It is in a nice neighbourhood in Friedrichshain with good transport links. The apartment was quiet and has all you need for a short stay (living room/kitchen, bathroom with washing machine and a double bedroom). It is a 30 min walk to Ostbahnhof station, however you can get the S Bahn from Landsberger Allee (10 min walk away) or you can use the trams for transport (M5 and M6 go to Alexanderplatz and other stations and the tram stop is 5 mins walk away). The bakery opposite is good and I also recommend the Viet Bowl restaurant on the corner. I did have trouble using Facetime chat on the internet there but Skype worked much better. I'd happily stay here again.