The room price published by Maria Letizia on Airbnb is 45 Euro. Which is how I payed online.
The receipt of payment received at the check-out specifies: 43 Euro for the room, and 2 Euro for accomodation tax of the City of Rome (look at here: (website hidden) ). I paid via credit card a total amount of 50 Euro on Airbnb: 45 Euro for the room and 5 Euro for Airbnb fees.
At check-out, when I was given the receipt, Maria Letizia asked me to pay cash additional 2 Euro for the accomodation tax (which I had already paid online), as she claimed that the 2 Euro paid online had to go to compensate her Airbnb fees (exactly 2 Euro). To my right grievances, in the end she said that was fine.
Finally, I did not make any negative comment about sharing the apartment: it was good to me, I was happy because the occupant of the other room lent me the shampoo that I had forgotten.
I made negative comments on the cleanliness of the apartment, which is something quite different.