I used www.limoservicerome.com on my last trip. Someone on FT recommended them and they were reasonable - 70,000 lira includes tip - and reliable. Driver was a young Brazilian woman; car was a Mercedes sedan.

My suggestions for a one-day visit to Rome:

Get up early and take a cab to St. Peter's. Marvel at the church's beauty and art work then take the several block walk around the corner to the Vatican Museums. Because you only have a day you'll want to move quickly, but you'll at least get to see the Sistene Chapel and skim the surface of the museum's collection.

From there take the bus to the Colisseum. Check out this structure then walk through the Forum. At the end of Caesar's Forum, below the church of San Giuseppe is the Mamertine Prison, where St. Peter and St. Paul were allegedly imprisoned. The prison had access to the main sewer and prisoners' corpses were thrown into the sewer. Stop in for a quick peak (it's small).

For lunch, pick up a panini to eat on the run.

Walk over to the Pantheon. Afterward, visit St. Ignatius on Piazza St. Ignazio, just two blocks away, and gaze at its amazing tromp l'oeil dome and illusionist-style frescoes.

In the evening, check out the Trevi Fountain and then stop for dinner at Grill and Wine on Via in Aricone or eat dinner at the St. Regis' wonderful restaurant Vivendo.

After dinner, take an evening passiegata to the Spanish Steps. Be sure and notice the Monster House along the way when you approach from the top.

Here's a link to a trip report I did in August with information about Rome, including a couple of restaurants we enjoyed. There's also information about how to request tickets for a tour we took in the crypt under St. Peter's. It's limited to 100 people a day and reservations must be made in advance. There are also some pictures, including one of the salon in our room/suite at the St. Regis. Have fun.

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