A huge thank-you to Maria! This place is really perfect for exploring Rome and - of course especially - the Vatican. The location is really quite good, 8-ish minutes to the nearest metro station Ottaviano, or simply walk to the city via the Castel Sant'Angelo.
If you head north-east away from the Vatican, the restaurants are quite good, with two grocery stores in the near vicinity.
The apartment itself was spotless, great amenities and good WiFi. The flushing of the toilet needs some getting used to, but works perfectly nonetheless. It fits three well; a group of four should still work, but it'll get a tad cramped.
We arrived quite early for check-in, but Maria had no problem with that whatsoever. Maria is a very friendly host and always ready to answer any questions.