We just got home two weeks ago from our cruise on the Galaxy - just wonderful.
We had all our arrangements made before we arrived in Rome for our 4 day pre-cruise stay. We booked transportation from romecabs.com, fabulous. On time, great rates and very helpful. Stefano got a lot of business from our message board and did a wonderful job accommodating what turned out to be a large group. He gave us tours in Rome, picked us up at the airport, drove us to our hotel, drove us to the pier to get the ship and returned us back to the airport to go home. You can reach him at :
allagrande@hotmail.it.
I woud suggest you find some others who will also be staying in ome for the night and coordinate dropping them off at their hotels. If you are sharing the cab fee with others the cost will be very small. I know the ship was charging $85pp for transportation. Our cab was only $125. Check it out, you won't be sorry.
Have a wonderful cruise