Walter's appartment is really great. You find everything there you need for short and even long stays. It is also very close to the trains, the regional ones (to the Airport) as well as the Metro. There are Carrefour and Todis supermarkets which can be reached within 5 minutes, and an 'Eataly' to buy food of higher quality.
When I arrived, Walter's mother came, showed me the appartment and explained where I can find the Carrefour (it is open the whole week 24 hours a day). She was very nice and friendly and told me all what I needed to know for my stay in the appartment.