We loved this apartment - it was beautifully central with trams right outside the door, bikes to hire nearby and easy for trains and buses too. It is well appointed and simply and well furnished for a short city break. We didn't need anything more! The stairs are not for the faint hearted but we quite liked the additional exercise!
Thank you both for communicating well with us and giving us such a good experience of Berlin. We would love to come back one day.