My wife and I had a very good experience and would definitely recommend it. The apartment is located very centrally- close to the Hauptbahnhof and walking distance from the city centre.
Note: it is part of a hotel - if I remember correctly, some previous AirBnB'ers weren't aware of that- so bear that in mind.
The apartment itself was exactly as shown- rather striking and very clean.
Bayram was very accommodating and easy to correspond with ( quickly answered emails). He was lovely in person and very flexible. He also allowed me park my car for an extra day and refused all offers of payment.
All in all a very positive experience.