My husband and I spent a couple of days in Tommaso's apt. It was LOVELY. we didn't meet Tommaso, but we were given the keys and directions from his mom, who was very sweet!
The apartment is really well located right on the central market street. I think this was on the edge of the turisty mass, while still being at a short walking distance to all major sites. The apartment was clean and exactly like pics (although if you are very tall know that you won't be able to stand up in the loft and bathroom. My husband is 5.10 and his head touched the ceiling. Minor detail since we spent little time up there!).
We loved our stay and definitely recommend!!