We stayed in this guest house for 4 days for a break in Hamburg. The good thing about this place is that it is central: only a couple of underground stops from the city centre while still in a quiet street. So far the good news.
In general, this guest house is neglected. You can say that quite a few years ago this may have been cutting edge. But now the rooms are simply poorly fitted, filled with a random collection of beds, cupboards, desks, chairs, lamp shades, pictures, curtains etc. Some old, some newer, some falling apart, some without purpose. It's not very clean either.
The breakfast room is quite cute with everybody around a single table and it's good that you can use the kitchen worktop, fridge, kettle etc at any time you like. But again, the room is such a random collection that you get a feeling this is a youth hostel kitchen/dining room.
The rooms are not en-suite. The shared bathrooms/toilets are average. Not very clean either. One of the toilets was simply dirty.
The photos on the website make the rooms look nicer than they actually are, we think.
In terms of service, it's not much better. Landlady is friendly enough (referenced to north-german reservedness). But you get the feeling that's she's really minimising the efforts after having done this for years. A few warm rolls/breads and a choice of teas for breakfast doesn't make it excellent. Some days there is orange juice, muesli. Other days it simply has run out.
Communication is really poor. We were put (without any sort of apology) in a tiny pockey twin room in the attick for the first night although we had booked a double room for 4 nights. Unacceptable. There is no written information on all sort of practical stuff and asking the landlady various things made us feel like we were a nuisance. Payment is by cash only.
In summary: this place probably used to be ok. Now it's simply far too expensive for what you get. Even in Hamburg,