The host met us in person although we arrived at late night and arranged everything, including help us with our transport to be booked from the airport. Tips were helpful.
The place to stay is very close to city center, 5 mins walk to train station but very safe and quiet, 10 mins walk to the Colosseum，4 mins walk to metro station. Besides, there are nice restaurants with quite affordable price nearby, with Chinese&Italian traditional favor well covered.
You will stay in a room with private toilet&bathroom, kitchen is to be shared, almost no people staying that you will meet though.