Emmhouse was terrific, literally across the street from the Vatican.
If you are walking from the metro station, know that it is kind of a hike. Up about a jillion steps after walking a few blocks, and then up a hill from there. Seeing Roma is alot of walking, but this was unexpected after a long tiring day of travel, so just be aware.
Marta was a wonderful host and the place is adorable. Shower is very tight if you are anything but a smaller person, beds are comfy, temp control was great, she even provides a selection of power adapters. we would definitely book again.