Great place, amazing location. You can do everything by walking distances: Museums, Dam place, stores, bars, restaurants, market to buy food (Marqt, Albert Heijn,..).
The place is very spacious and well decorated. Being a music fan, Maarten has a very nice collection of vinyls and great sound system in his flat. The bathroom is amazing with a full shower and bathtub. The kitchen has a gas stove and nicely equipped, great if you like cooking.
Be prepare for the steep stairs case especially if you carry heavy luggage but it is part of being so center so totally manageable. The apartment is on second floor so you can hear the neighbors a bit at evening/night.
Maarteen was really helpful and responsive.
My girlfriend and I totally recommend this place for a amazing trip in Amsterdam.
PS: if you love seafood, try "The Seafood Bar" on Van Baerlestraat.