Ciao,
We had a great week there!
Mario was on time to give us the key for the flat but I guess he is a busy man as we couldn't really chat much.
The flat is cosy and at the first floor so it's cool when you come back from the grocery store ;)
The accomodation was really fine, looks like the picture! Except that we had 1 day without hot water/ Heat.
You'll also find a list of place to go nearby, the metro is not even 5 mins walk so you'll reach it easily. If you go to trastevere, you'll need a cab to come back at night because it's kind of far away (count 11€ for a ride).
It's a fair deal!