Serena arranged for a very efficient, friendly, and reasonably-priced taxi driver to pick us up from the airport, which was a huge help as we were travelling as a party of five (with elderly parents and a toddler). Valeria was on hand to greet us at the apartment; the legendary cookies were also waiting for us - they went down especially well with our two-year-old! - and there was milk in the fridge, for which we were grateful. Valeria was on hand via text message throughout our stay to offer help and advice. (This was especially welcome as we were in Rome on the night of the earthquake in Perugia, and we felt it and the aftershocks in the apartment.) Serena also arranged a comfortable cot for our daughter, and I rearranged some of the lovely ornaments in the apartment to keep them out of reach.
Our stay wasn't long enough! We'll be back, I'm sure.