ZOOM!
The Alfa Romeo 147 (or similar): $1602.60 + $2.50/day road tax
via
AutoEurope
We'd looked into leasing cars which All The Guides say is cheaper. Apparently the two bigguns for Italy are Peugeut and Renault. Renault leases are available through AutoEurope for marginally cheaper, but by the time you've included the to/from France travel charges ($150/ea), it didn't look like such a deal. In checking with Reneault's website we found that they were only marginally cheaper but required a 30-day pre-reservation, no good for Last Minute Charlies such as ourselves.
Sure we had other options, but c'mon: Fiat or Alfa Romeo? Its a no-brainer.
Addendum: Roy and I both ended up getting Fiat Stilos, the Jetta of Italy. It was a pretty nice car to be tooling around in. I found it capable and easy on the gas consumption, a nice vehicle even if pieces were falling off it, which they were.
AutoEurope has branches in most of the airports, but for my transaction (at least) they acted as brokers for Europcar (strangely enough). A decent transaction all the way around I thought -- the incidental post-checkin charges were minimal.