The apartment was great and the location was so central! We walked most days but when we did go a bit further out it was really simple to get back thanks to a U-Bahn station and also a couple of well-connected bus stops very close. Is is a 5-8 min walk from Gendarmenmarkt which was our favourite of the Christmas markets so we ended up spending a few evenings there.
Jose was very helpful with information and provided great instructions as to how to get to the apartment and also lots of information about the local area and recommendations.
The apartment itself is compact and was clean. There is a bathroom (with the best water pressure I think I have ever experienced(!) ), a small kitchen which overlooks the Airbnb room, and then another room which Jose sometimes has relatives staying in which was locked. Although there was someone staying in the other room over our 5 night stay we were out most days and so never actually bumped into them! Jose lives on the same floor in the apartment block so was there to hand us the keys on our first day and was only a few doors down in case of any emergencies!
I would definitely recommend this apartment and look to stay here if I ever visit Berlin again! :)