We stayed at a 4Bed Room in the Singer Hostel Berlin and we loved our stay there. The room was spacious with big windows, and a personal bathroom - everything was clean. The room was quiet - we heard no noise from the street or from the hostel itself. The check in was open 24/7 so we didn't have any problem with our late check in (we arrived at 2am). The staff was very helpful and the common areas of the hostel were pretty nice too. Accessibility was not a problem, as an Ubahn line is very close, and Alexanderplatz is like 15-20min away by walking. We would definitely recommend the place!