you have several choices to reach the house from the air terminal Leonardo da Vinci .

Fastest :
from the airport train station you should not take the Leonardo Express which goes directly to Termini, the main railway station of Rome.
Take the local train (every 15 minutes) direction Fara Sabina / Orte , until the sixth stop , Trastevere where you can catch another train to Roma SAN PIETRO ( one or two stops , depending on the train towards Cesano / Viterbo Civitavecchia / Grosseto) . On leaving the station Roma San Pietro , take on the left the underpass , then exit left, next to the Orthodox church of St. Catherine , you've arrived.
Ring the intephone B 8 , Angela will come down to welcome you.
The train ticket costs 8 euro per person. Do not forget to validate your ticket in the yellow machine before boarding the train .

Most touristic :
Take the shuttle bus Terravision (you can book on line : www.terravision.eu , price € 6) to Termini Station . On the square of the station, take the bus n. 64, price € 1.5 , and get off at Place of San Pietro Train Station . This bus runs through the center of the city and will be the preferred transportation during your stay ( the line is very popular with tourists, but also by pickpockets !) .