Marco's apartment is very close to the tram that takes you right downtown Milan, but it does take about 20 minutes to get there. The tram also runs late at night, which was very convenient for us.
Marco is a very pleasant host that know Milan very well and will gladly provide you with tips and places to go. He even provided us with a transportable WIFI router that became very useful for us in the city :)
The room is in the basement and therefor has a nice cool temperature during the hot Italian summer months. However, the room is not closed off with a door, but open because of the staicase that leads upstairs, which would have been nice to know beforehand.
Check in and out is very flexible which is nice and Marco was at home when we arrived to welcome us. However the communication about arrival was a little complicated because Marco is so busy with his work. But it all worked out in the end.
The neighborhood is nice and safe. Even though it is a bit far from the city center, it has everything you need nearby (cafe, bar, pizzaria, supermarket, ATM).
All in all, we're happy with the stay and would definitely recommend it to other travellers visiting Milan!