The hosts greet you at the door, tell you a bit about history of the place, and provide you information about Florence. We rented the place for a week - they checked in with us during the week to make sure we were okay. The hosts help you find a taxi at the end of your trip. They did all of this without being intrusive. We appreciated their efforts greatly.
The apartment itself is centrally located. While it is in a historic building, the interior is modern with high end furnishing and a nice design. The master suite has especially nice features, including a bath with jacuzzi style features. The air conditioning was especially great, given that it was 30-35 Celsius outside.