Rosie's flat is lovely, with the typical narrow and steep flight of stairs, but that is just common in the Netherlands... it is in a really quiet street, at walking distance from the Museums, and with easy links to the center. Actually, Rosie has lots of good indications on how to get there and around. I walked from the Station Zuid, and found it a very easy and fast way (my suitcase had wheels, and it was less than 15 min).
The room is very comfortable, the bed is really nice! with the added detail of a blind, which really helps us southerners to sleep during the short Dutch summer nights! It also has a table and a chair, and perfectly working wireless!
The guests have their own bathroom, with a shower, all modern and cute.
I strongly recommend this option for anyone visiting Amsterdam, and I'll make sure to go back myself!