Summary - Stayed for a month at end of August, first 3 weeks of September. Excellent location, very large space, had a couple of minor issues but would rent again!
Getting there - 58EUR fixed rate from the airport, 35mins, you can pay by cc on all Rome taxis.
Location - one of the main streets of Monti, very picturesque. Couple of restaurants nearby. 15 minute walk to the rail station if you want to visit Florence, Venice etc. 10 minute walk to the Colosseum, 15 mins to the Fountain, Pantheon, Spanish Steps etc. 30 Mins to Trestevere. So, very well located on the east/central side of Rome. If you were in Rome for 2 or 3 days you might want to go more central, but if you are there for a week or more then this is very nice - less crowded than the center, yet easy to get where you want. Kind of a locals/hipster/tourist area. Cool.
Check-in/Apartment - met Luca, who ran a little late by US standards (15 mins) but right on time for Rome :-) Lovely guy, very helpful and friendly. The apartment has an elevator but we only used that initially for getting luggage up the stairs - after that it was 2 short flights (1st floor in Europe, 2nd in US, i.e. 1 floor above ground floor). Very large space, like huge. Could be a 2 bed apartment tbh, but the living area takes most of the space, and the bedroom is a good size (there's a small single bed actually in the living area if you were 3 people). Small kitchen, plus 2 bathrooms, 1 ensuite, the other down the hallway. Washer/Dryer in the hallway bathroom (but the dryer heat worked erratically - see later). Ensuite bathroom is stand in bath, hallway is stand up shower.
Specific pros/cons
Bed - nice double mattress, one of the foam type ones. Pillows, as is usual in Europe, kind of lumpy but not bad at all :-)
Living area - good table for working on - plus chairs. Easy to setup 2 laptops plus headsets etc.
Kitchen - pretty basically equipped, but clean, and now has a coffee machine! (We drink a LOT of coffee so we went and bought a single pod style machine so we could dose up on caffeine!)
Showers - I see elsewhere people complaining. They were indeed terrible at first, all blocked up and the flow was bad - but Luca came with two guys and, with a minimum (for Italy) of hand waving and shouting, all fixed up! There are now two brand new rain style shower heads, plus plenty of hot water anytime - 5* hotel standard showers/hot water now!
Wi-Fi - I also see complaints about this and, tbh, it's so so. There is an ADSL line next door, connected to a range extender in the apartment. Strange setup, and leads to lowish speeds (10down/0.5up) plus drop outs 4 or 5 times a day. So, if, like us, you are working and doing zoom meetings back to the US, it was, tbh, not great. If you are a normal person on vacation who just wants good Wi-Fi for your phone etc., it's plenty good enough. I'm in high tech and screen sharing + video was definitely a challenge, especially for a month. This was really the only major downside of the apartment.
A/C - really good. In Europe that is not always the case because they use wall mounted units. But they (2 units) were quiet, efficient, reliable. Really excellent.
Washer/Dryer - really a washer is advertised but it is actually a dryer also. But, the dryer part keeps flipping off. Really needs to be fixed to be reliable, OR just accept that it doesn't dry, and use the in unit drying rack, which is what most Italians do anyway I gather.
Uber - you can call a taxi via uber or call an upgraded Uber black if you want. $11 in a taxi to Trestevere, $19 in Uber black, but like I say, you can just use the one app.
Shopping/eating - great supermarket 2 doors up, plus restaurants all around. Shopping Rome in general is unbelievable - very inexpensive for everything - jewelry, clothes, food etc. And nice people as well. It would be worth visiting Rome just to load up on shiny trinkets, and my wife did!
Ok, that's it, again, I want to say that we were there for a month, so some of the things which were annoying for us (Wi-Fi, washer/dryer) would be very minor for others. I loved this apartment, I loved the area, I love Rome and Italy, oh, and Barbara was very nice and communicative also. All in all a great trip!