The appartment is very nice looking and looks even a bit bigger than it seems in the pictures. It is located near a busy street so that can give a lot of noise (it is ok when wearing earplugs). It is a 50 minute walk to the old center but very close to the metrostation Westbahnhof from where it is a 10 minute ride to the old center. Check in and check out was very easy.
A little downside was that the WiFi stopped working after one day.