The place is in the city Center. As the metro network is not very comprehensive in Napoli, 10 minutes walking from nearest metro station is expected. However, if you would like to go to Amalfi and Capri, the pier is just next to the bnb. So it is convenient.
You can get some great tips from the host in regards of food and transportation.
Generally, it is a perfect stay in Napoli with the super quick respond from the host. I enjoy the hospitality by his whole family:)