My husband and I stayed at Derk's boat for three days in December and absolutely loved it! We found the place spotless, with all the necessary amenities (good coffee maker, hot shower, great bed, wifi.. etc.). We felt at home right away and couldn't get enough of the views from the boat onto our peaceful canal... I mean, you can see the towers of the Rijksmuseum from it - you cannot beat that!
It is a great place to explore Amsterdam. There are tram stops close by, a grocery store 5 minutes away, nice cafés and bars close by too. Derk is a great host, easy to communicate with and very accommodating. This is a very special place to stay in and I highly recommend it.