My mom and I stayed at Marco's apartment for five nights and had a great experience. We flew in early and Alessia met us before check in so we could leave our bags, gave us an overview of the place and great tips on the neighborhood and where to eat.
We loved being just a few minutes walk from the forums yet out of the way enough to avoid all the tourists. We walked to the Colosseum, Trevi, Spanish Steps, Campo di Fiori, Pantheon, and Trastavere with no problem. We also walked around the Monti neighborhood quite a bit and always felt completely safe and comfortable on the streets.