We decided to spend three nights in Cortona (at B&B Gelosie) in July and I wanted to let others know that this car companyoffers daily rentals if people are in this area of Tuscany without a car (like us!). Tania, who just moved to Cortona for a year (and has a great blog), turned me onto the site. The rates looked decent, about 50-65 euro per day and they will bring the car to you in the area.
Now we will be able to more easily take a day trip around to see Montalcino, etc.
We are going to be in Tuscany in June and found out that you can also reserve daily rental with Hertz. They only allow you 100 km for free instead of 150, but the rates are pretty good.