Overall great experience staying in bens apartment. He was super quick replying to all messages and was very helpful and informative about how to get to the apartment.
Although we never met Ben he made sure a friend was there to give us the keys and left notes for everything such as wifi codes and even recommended places close by for food and drinks.
The Apartment is in an old building but is spacious and warm and only a 2/3 minute walk to the u-bahn. It has everything you'd need for a short or long stay in Berlin.