I want to say that this place has a lot of character and is a great stay, but there are more fees and conditions in the description than are usual for an AirBnB listing - so, I want to foreground those to help other renters. It's clear other people have had issues understanding the listing, so something should be done about that. These are all things that are in the listing, but some of them are far down, and other people have missed them too.
EXTRA FEES for arrival at different times. Understandable for late-night arrivals, but weird for Sunday morning. We missed it, it's fine, but we should have gotten a message sooner than the day before.
LOT OF STAIRS. Be wary if you have lots of suitcases.
AIR CONDITIONING is extra. This is a big deal in a Roman summer. We decided to go without, but were pretty miserable at night. Wouldn't advise if nighttime temperatures are 70F or above.
The listing also advertises a magnificent view of the non-Catholic cemetery. This wasn't a game changer, but it's not very accurate. There's an institute with sports fields across the street, and beyond that you can see the trees of the cemetery, but you'd never know that's what you're looking at, or that it's anything unusual.
But that segues nicely into the positives! The location is wonderful, and we did finally see the cemetery where Keats and Shelley and Gramsci are buried. We also got to stay in one of the best neighborhoods in Rome with one of the best selections of restaurants. You can also easily jaunt to Porta Portese (and easily escape back when it starts to feel hectic) and you can explore the beautiful nearby hilltop neighborhoods of San Saba and Ripa (with the Giardino, degli Aranci, one of the best views in Rome). It's a very doable long walk to get to the main tourist sites, we rarely used public transportation. And it will be easy for you to pick a favorite neighborhood bar to have your morning caffè.
The apartment has a lot of charm. It's not that awful kind of AirBnB that doesn't feel at all lived in and just has a few pieces of IKEA furniture. There are a few things that should be fixed, like a bit of mold in the seam between the floor and the tub, but mostly it's very livable. The mattresses on the beds are just firm enough. The sitting area is fairly comfortable. The windows on two sides of the apartment are magnificent. There's a nice amount of closet space. The kitchen is well equipped. The cleaning was fantastic. The lighting in the photos makes it seem A LOT brighter than it ever is at any time of day, but I loved the actual lighting in the apartment, which was magical and moody.
All in all, a nice stay, but with the way AirBnB jacks up prices, it ends up being a bit expensive for the quality, and so the extra fees start to make it a questionable value. Still, if you like Testaccio and you prefer a place that feels a bit lived in, this is a good choice.