Dietrich was very helpful with booking. During our stay he checked that everything was okay and he provided handy travel information and suggestions for restaurants etc. There were three of us staying so the apartment size was perfect. Dietrich recommended a nearby german restaurant which was very welcoming enjoyable. I would recomend a hop on hop off tour bus if you only have a short stay to get to know your way around the city. Three companies were all trying to sell tickets so haggle for a better price than advertised. We also went on an alternative tour of berlin street art which was excellent!