Unbeatable price for Hamburg. Less than two minutes from subway which takes you to the city center in under 20 minutes. That being said, the district where it is located (the Ha-r-burg part of Ha-m-burg) is VERY worthy of exploration by and in itself - my favorite hood in Hamburg because of its cultural diversity.
Super friendly personnel, including cleaners. Front desk opens at 11:00 am and (I think) closes around 9:00 pm. If you have a key, no problem, but I am not sure how late check-ins are handled. You can check out before 11:00 by dropping the key in a key box, but you won't be able to come back in.
NO ELEVATOR, and no breakfast when I stayed there (plenty of cafes and bakeries around, though).
The only downside was the bed which was not very sturdy and constantly moved around. The mattress was comfortable, though.