We stayed at Mirta's for 1 month. From the start Mirta was very helpful. Before we had arrived she had helped us set up childcare for our 3 year old, advised us regarding soccer tickets and answered all our questions truthfully.
We loved the liveliness of Trastevere, the friendly people of the neighbourhood and the ease of having everything right out our doorstep. I don't think you can beat the location.
The apartment is as pictured and everything works well enough. The steps are challenging and so are the many different levels and head heights in the apartment but if you are fit and able it's just pRt of the experience.
For a stay of one week or so we would highly recommend Mirta's and the suburb of Trastevere as a base for exploring Rome.
Pros: apartment was very clean, and the shower was excellent,
assistance from Mirta, Lavinia and Joy invaluable (we are so grateful),
Excellent proximity to great inexpensive restaurants, coffee shops, bars, live music, fresh bread, daily fruit & veg from the markets, fish, meat, grocery stores and pharmacies.
Music drifting in from piazza trilussa and being able to see the lively square from the living room window
Being moments away from Ponte Sisto the beautiful Tevere and the historical centre of Rome
Buses and trams are close by, reliable and will get you anywhere you need to go in Rome (very useful for us with a 3 year old)
Cons: there probably aren't any if you only have a short stay but if you're a non smoker you may not like the smell of cigarette smoke coming through to your apartment from the floor below and the beds got a little uncomfortable after a week.