We absolutely loved our stay at Guendalina's place. It is clean, quiet, and has everything you would need for a stay in Rome. The outdoor patio is beautiful and relaxing and Guendalina is a great host- she is responsive and helpful and communication with her was a breeze. As for location, you will need to make use of tram 8 for all things in the historical center or a quick train ride from Trastevere station for the Vatican as it is a bit too far to walk easily to all those places. Outside of that, we loved our stay here.