Alexander's flat is great, even better than the pictures, we felt right at home. The flat is bright, modern, equipped with everything you need, we were even welcomed with a bottle of wine and chocolates. The location is very good, right next to Vondel park, 15 min walking to Van Gogh museum, a lot of trams to go pretty much anywhere in Amsterdam and on the street there are a lot of bars, super markets, restaurants and we were even able to find parking right in front of the building even though it was a holiday and so very crowded.
We did not get to meet Alex, but the key exchange went smoothly and he made sure we had everything we needed.
Definitely recommend this place if you're in Amsterdam.