A fantastic apartment in a very quiet area - we didn't hear a thing at night.
As others have said the location couldn't be better - a few minutes walk from Westbahnhof. There are plenty of bars and restaurants nearby.
There is a supermarket about a minutes walk away (shut on Sunday but plenty of food shops, including bakers, open in Westbahnhof station).
The apartment is spotless and really well equipped - every kitchen implement you can think of seemed to be available. There was a good supply of coffee capsules as well.
Our welcome was really friendly and informative.
Natascha is very accommodating. When we let her know what time we were arriving, she suggested that even though we couldn't check in, we could leave our luggage there until we could.
Would definitely stay there again.