Everything went really fine. The contact was really easy, first airbnb then with the phone and he was flexibel for the time to give us the key. We got really helpful instructions to find the flat and were welcome really nicely.
The flat was much bigger than we expected. It was clean and cold which was really nice according to the weather :) We could contact him whenever we needed something and the whole stay went so good.
The location is also really nice - only 5 minutes to the metro stop and from there you can easily reach everything.