My friends and I stayed at Dan's place for a couple nights and it was perfect. The location was easily accessible, even from the airport, and the nearest U-Bahn stop was just a couple minutes away which took us right into the city centre. Entering the place was very simple too, all the instructions were sent to us by email and we had no problem using them. The flat was quiet, really clean and such a cozy place, very sunny and very warm which felt good during chilly evenings in Berlin. We were provided with tea and coffee, bedding and towels and suggestions for the city which was again a nice touch. Check-in and check-out are also at comfortable times so you don't need to rush in the morning. The value for the flat was also great, even if you are not a fan of the city centre, you can find so many things to do in the area, including the old airport and nice food shops. I would absolutely recommend this place to everyone who is looking for a nice and chilled stay in Berlin, you will have the best time here!