Hi all:
In 2 weeks i've be in italy. Thing is that i will travel by car from firenze to Rome. But. I have to 2 days free. So i want to go to TUSCANY. Spend a whole day, stay overthere, And leave on second day by noon. So please any advice about what to see (wineyards, olivia,) and where to stay (I'm on a budget). Will be great.
Thanks in advance!

When you're in Florence you're already in Tuscany so you don't have to go there - you are there.

Rather than renting a car why not look into day trips from Florence, either on your own or escorted. It will probably be less expensive than renting a car for 2 days. You will be able to take the train to Rome which will be a lot less stressful than picking up and returning a car in cities.

If you do decide to rent a car then the San Quirico, Pienza part of Tuscany is very pretty. Depending on when you're going the olives and vines may not be mature.

I wouldn't rent a car to drive from Rome to Florence. Parking and dealing with the pedestrian-only zones in Florence is a mess. Is there a special reason you need the car? If not, do as Adrienne suggests and take a day trip to the Tuscan countryside.

If you want to see the Tuscan countryside rent your car in Florence. Drive out of Florence and get on the SS 222 to Siena. This will take you through rolling countryside, vineyards, olive groves and small towns. You can stop along the way in any town you like. When you get to Siena you can drop the car and take a train to Rome. Or, continue on to Orvieto if you have a Hertz rental. There is a dropoff near (but not at) the train station. There are trains into Rome every hour. Spring is the best time to do this drive. You may be a little early but the colors in spring are spectacular.

Driving from Florence to Rome is both more expensive and much slower than taking the train.

Flinn's idea is a good one, but check the hours the rental agencies are open. The smaller agencies often close for a few hours in the afternoon, and may not be open at all on Sunday. The rental agency in Orvieto is near the station, but I'm not sure that's true in Siena, so check that also. Chiusi is another place where people often drop off rental cars to take a train to Rome, but I know that agency is closed on Sundays.

Thanks to all for your kind responses. I forgot to mention that my trip starts in Milan and ends at Rome(15 days).That's why I have some spare days. Again Thank you all!!