My girlfriend and I stayed on Derk's boat for 3 nights, and we wish we could have stayed for more. It is a wonderful and unique experience that both of us will never forget. The boat itself was very spacious and well-kept. Derk was very friendly and offered to help at anytime if a problem arose (which none did). We would recommend this boat to anyone who is looking for something a bit different than the usual hotel experience. Hopeful one day we can return to Amsterdam, and if we do we know exactly where to stay.