The apartment was lovely, exactly as advertised. It was a great stay in a great neighborhood. Guilia is a responsive host, although we didn't get to meet her in person; her boyfriend met us at the apartment to let us in and give instructions. (He was nice, too). Giulia clearly actually lives in the apartment (it is not an unit that has been taken off the market to be rented out exclusively) and it felt homey and like staying at a friend's place.
Tessaccio is a lively, not terribly touristy neighborhood. It's a great place to stay if you want a glimpse into real local Roman life, but still be close to all the tourist attractions of Rome to walk or hop on the bus or metro. There are great restaurants and markets in the neighborhood and your excellent caffe will cost you less than 1 Euro at the counter at the local coffee bar! Also a bonus, there is an elevator (tiny) to send your luggage up the stairs in. We opted to walk up!
My only word of caution is that the bathroom, while beautifully remodeled and clean, is extremely narrow. A person of size would definitely struggle with it. Small bathrooms are the norm in Italy and Europe in general, but this one was very narrow.
This was a very positive experience and I highly recommend the apartment.