I stayed for 4 nights to attend a conference at the world forum. Marlenes place was fantastic. A huge room with comfortable bed. Great shower and well equipped kitchen. The world forum was only a short 10 min walk away, the street and the area was pretty and safe. I hardly saw Marlene, you wouldn’t even know she was there! The house was very quiet.
Getting there from Amsterdam the airport via train to central station and then Tram 16 was super easy. The city centre was about 30 mins walk or 15 mins on the tram.
The only thing to be aware of is the apartment is on the third floor up steep stairs. If you have a heavy suitcase this could be a problem for some.
If I return to this conference I would definitely chose to stay here rather than a soulless hotel room.