We stayed at Gert's for only one night in May.
Gert was very accomodating for the check-in and the check-out, and very friendly to explain things about the apartment.
The aparment is clear, clean, very confortable and calm.
It isn't situated in the center of Amsterdam but it is very near from the P+R Bos En Lommer which might be the best and cheapest way to come in Amsterdam by car.
It's less than 15 minutes to go down town by tram (7 or 14).
We can see the Erasmus Park from the apartment.
To sum up, a nice place to be to visit Amsterdam.
Thanks again Gert :)