I've stayed in several Airbnb, both in Milan and elsewhere. Carmen's apartment is definitely the best stay in Milan and possibly the best overall.
A typical Central-Milan Airbnb is room in a shared apartment facing a thoroughfare. Except when you are facing the railroad. Carmen offers a whole apartment where the only noise is the occasional steps by a neighbor or garbage collection.
The apartment is tastefully with old pictures of the city and offers kitchen, TV, bathroom band a washer. The location: 5 minutes tram ride from the the Station (you want to avoid the metro when carrying luggage: Milanese turnpikes are formidable opponents) the area brims with character. I counted restaurants from ten different cuisines, two supermarkets and a neighborhood market full of gourmet stalls. No need to eat out: just bring home the market's goods.
What sets the stay apart is Carmen. She puts "Customer Satisfaction" to a new level. In the apartment you find: water, juices, wine, beer, snacks, and something else I've forgotten. She let me drop the luggage early. She even carried my wife's luggage to the tram stop five minutes away!
I'm going back next month and Everytime I'm in town