I stayed at Mario's house only one day, but I can say that it was a great experience. Everything was more than perfect. Mario offered also to pick me up from the railway station and let me keep my baggage at home for some hours more. The house is close to Federico tower, but not close to the other hot spots of the town. But the town is not big, so one needs just 10-15 minutes walking to the furthest point. Absolutely recommended.
Grazie per tutto.