This is really a once in a lifetime stay. It comes with its drawbacks— a little far from the places you’d want to visit on the quintessential Amsterdam visit, but being on a houseboat made up for that in our opinions. We had 3 people and fit perfectly. I think you squeeze fit 4 but definitely no more than that. The wifi barely works and the top bunk is very narrow, but we had a great visit and are extremely glad we decided on Ton’s place :)