Perfect large room in a B&B (2 rooms in total + a shared kitchen) : super nice, well renovated, clean and airy. You can easily walk to all the sights and it's really safe to walk at night (I was a solo traveler).
The place is in the heart of Trastevere so yes, there's always people on the street late at night and yes it's busy and noisy. But you're in the middle of the action and the windows are soundproof. So no worries, just close the windows at night, put on the air conditioning, and you'll sleep like a baby. The shower is big and good pressure of the water, which is very nice!
Vanessa was very nice and took the time to explain everything.
I highly recommend this place to anyone who want to discover the beautiful Roma. I would go back anytime!