The location is terrific. It can be very loud outside, but inside it is calm.
I never met Fab in person, only his colleague, but he was very quick to respond to messages. I'm not sure he's the owner of the flat either, but it seems very official since you have to pay the Rome tourist tax.
The apartment is well stocked with lots of surprises: endless amounts of tourist brochures and maps, drinks, simple breakfast foods and coffee, even hand painted water colours for sale.
At first I was apprehensive about staying at an apartment that has had so many guests, but it all went smoothly.
I would recommend it to friends.