We have just spent three nights in Diederik's apartment. Diederik was very prompt with all communication and provided useful information prior to our arrival. He was also very understanding when we arrived late due to delayed flights, and provided great local knowledge on restaurants, cafes and sights. The apartment is in the best location - we were able to walk everywhere we wanted to go in the city. It is very comfortable, cosy and has everything you could possibly need - including very useful umbrellas. It was a great stay and I highly recommend Diederik and his apartment to anyone travelling to Amsterdam.