Very good stay in Amsterdam !
Cassia who welcomed us is really nice. She gave us a map and showed us many tips and advices about the city.
We shared the place with cassia and another sympathetic traveler from San Fransisco.
The free acces to bikes is a big advantage to travel aroud the city, we especially liked this bed&bike fomula. (Stefania's flat is about 15 min to the city center)
I recommend 100%.