Serena has an excellent apartment about 10 minutes away from the Vatican by foot.
It is by far the most impressive Airbnb I have ever had the pleasure to stay in.
The place reminds you of a business hotel, with all the amenities needed for a comfortable stay including a fridge and a microwave.
I really appreciated the small touches of espresso pods and bottles of orange juice in the fridge.
Serena is a fantastic host, and was very prompt with her responses.
I would very strongly recommend staying at her Airbnb if you're looking for a place to stay near the Vatican. I had an excellent experience.