Although the flat is located outside the centre, both metro-train stations are in a short walking distance (10-15mins) and from there it only takes 20 minutes to get to the city (with OV chipkaart such travel costs around 3€ which is OK).
The rooms are just as on the pictures - very well equipped and clean. We had everything we needed.
The communication was smooth, we were always informed about the check in-out times and got many instructions regarding the keeys ect. In our room there was even a little guidebook with all the useful information included we might needed throughout our stay.
All in all we had a great experience in Amsterdam thanks to the accommodation provided by Francois.