Car rental

Firstly, I would ask your travel agent if she is using AutoeuroA or AutoeuropE. The one ending with A is a horrible company and should be avoided. Autoeurope, ending with an E, is a very good company.

My concern with the garage is that it may be in a ZTL. If that's the case you need to get specific directions form the rental company and follow them to the letter. If you deviate from the specific route you could be heavily fined for straying into a ZTL.

I would drop the car off at the airport and take either a taxi, transfer or train into the city.

Donna

Get back with your travel agent and ask them if the address of the rental office is:
Via Sardegna 30 A
Rome, Italy, 00187
Phone: +39 06 3216886
If so, it's a Hertz office.

I usually use AutoEurope.com or Hertz directly for rentals in Italy, specifying location I know is Hertz'. I prefer to do business with Hertz as they're company owned in Italy--not a franchise.

Many rental cars are left at the Orvieto Hertz office north of Rome. The office is across the street from the train station, and it's a 70 minute ride into Rome Termini.

I'd be surprised if a TA booked through AutoEuropa as Donna's correct - Auto Europa is a poorly rated company. That said, Via Sicilia,9/13 is a drop-off location for EUROPCAR and is located at the Westin Excelsior Rome parking garage. This location IS outside the ZTL areas of Rome by about two blocks (if you come from the north, off Corso d'Italia). If you're coming from the south, it's more challenging to avoid the ZTL's.

We are using the better company Autoeurope. If the drop off is at the Westin is that a very difficult place to get to if we are coming from the north. For some reason our travel agent did not want use taking the train from Tuscany to Rome. Should we try to find a different place to drop off. If we wanted to change the drop off site can we do that when we pick up the car?

It's not any more difficult than driving in any other large city. A GPS will be useful.
The Europcar locations easiest to reach from the freeway coming from the north are probably the one on via Flaminia Nuova 216, or also the one on Via Tiburtina 905.
If you want to drive closer to the city center the Tiburtina station is also not difficult. Both are open Mon-Fri 08:00-20:00 (with break at lunch) and Sat AM. From either take a taxi to your hotel in Rome.
Just don't get to Rome during morning rush hour when commuters drive into the city.

Also you don't need to return the car where you originally booked to return it. Even if it's booked to return at the Westin Excelsior you can still return it on Via Flaminia Nuova. I book from Europcar all the time and return it where I feel like. Sometimes even without calling ahead.