First of all, Roma station Code is XRJ.
Second of all, in the summer of 2018, I went to Italy with my wife and, after landing in Bergamo Airport, we had to decide how to get to Mantova (it's close to Verona). After checking prices for buses and trains, I discovered that both ave very expensive in Italy. Actually, we ended up paying less for a rental car than for a train (2 people round trip would have got us to approx 450 euros), while the car was approx 300.