Communication: Marco will overwhelm you with extremely long instructions and then get mad if you do not arrive precisely on time. He was rude and was shouting at me in the street because of a delay because google maps took us to the wrong location (don't just copy the address into google maps - it took us to south Milan about 25 minutes away by subway).
Accuracy: the apartment is one bedroom and one pull-out couch. 1, not 1.5 bath, and very small. It is listed for five people, but I don't think you could possibly fit that many in the space and I certainly didn't see a third bed.
Check in: despite what the listing says, you do need to specify a precise arrival time several days before you get there. Plan for a half hour for Marco to explain how everything (from the pull-out couch to the breaker box) works.
Otherwise, the apartment is in a great location for access to the old parts of the city and is a fun space.