Everything was good, Letizia gave us clear instructions for arriving and let us leave our luggage before the check in time. The appartment is not big (good enough for 2 girls, but for a couple with a tall man using the bathroom will be a bit uncomfortable, because it's very small), well equipped, except the electric kettle (there were even different species) and clean. Especially we enjoyed the small balcony, of course, with no city view, but cozy to drink our coffee and to smoke (that's important for smokers, smoking is allowed at the balcony). The best thing is the location, very close to everything you want to see - piazza Navona, Campo di Fiori, The Pantheon, Spanish steps, Trastevere - you can reach everything by foot. There are different supermarkets near the apt (small, but you can find everything you need), tavernas, shops with clothes and souvenirs.
We are thankful to Letizia for our staying and recommend the appartment to other future guests.