I went to Berlin and stayed at City stop in early June for three nights for the Carnival of Cultures.
I was pleasantly surprised when I first arrived inside the building, with its apartment look and communal area, I was more than happy with my choice. Each room has an amazing en-suite shower and though it may be small the shower itself is glorious. The communal kitchen has all the pots, pan and utensils you may need and well as free tea, coffee and herbal tea selections.
As my booking was late I had to change rooms the three nights I was there. The twin room for my partner and I was not ideal but the room was spacious with cable provided on the flat screen TV. The single room we had on the second night would have been perfect for a single traveller as it was extremely small but liveable but for my partner and I it was unbearable- I found myself sleeping on the floor.
The staff there, I believe, mad my experience what it was. They were friendly, funny and gave advice when ever needed. They were there whenever you needed help and seemingly vanished when you needed space. There was never a sense of overcrowding even though there were 10 rooms.
Though it is self-catering - there are many delicious places just down stairs where you can eat: Burger King, Turkish Grill, Kebab House, Cafe, Chinese, Pizza and a conveniently placed supermarket and green grocers if you do like to cook.
The underground to everywhere in berlin is a hop and a skip away from city stop and the town centre is a short walk if you'd prefer to look at scenery.
Altogether I would definitely recommend this place especially if you are travelling in a group.