Apartment with very nice outdoor terrance in the Trestevere neighborhood. It's a 2 minute walk to the metro. It's about a 10-15 minute walk to get to the heart of the neighborhood with all the bars and clubs.
Got many recommendations for places to go eat and see when I was there. I enjoyed my stay and would stay there again.
One thing to note is the shower. If you're at least an average sized guy the shower curtain can be a nuisance. I'm 6' 1" and it was on top of me.