Florence Italy Car Rental

Yes, the pick up at the airport location is always more expensive.
Hertz in Florence has 3 locations:
-Airport (North West of the city)
-53 via del Sansovino (west of the city center, south of the river)
-137/Red Borgo Ognissanti (inside the Historical Center)

Check the following consolidators for best pricing:
www.autoeurope.com
www.kemwel.com
They work with the major companies including Hertz and usually at better prices than directly.
If the 5 passengers are all adults it might pay to rent 2 economy cars, because renting a minivan costs as much as 3 economy cars. But as I said, check price options in the 2 websites above (actually they are both part of the same corporate group, so they work similarly, although prices may differ)

A few points to note.....

• each driver listed on the rental form will require the compulsory International Driver's Permit, which is used in conjunction with your home D.L. You can obtain these easily at any AAA office, and they're valid for one year.
• you'll need to be extremely vigilant to avoid the ZTL (limited traffic) areas, as Florence is almost saturated with automated ZTL cameras and each pass through one will result in hefty fines.
• rental vehicles will most likely have a manual transmission, so if you can only drive auto transmission that's something to keep in mind.
• you'll be required to purchase a portion of the insurance from the rental firm.
• you'll also have to be vigilant to avoid the automated speed cameras, as they don't usually give much / any leeway.
• automated fuel pumps may only accept Chip & PIN credit cards.
• be sure to budget for tolls on the motorways.
• A GPS or at least a good map would be prudent.

Ken made some great points. We stayed at an agriturismo south of Florence and took the bus to the city. From what I saw of the traffic, there's no way I'd want to drive anywhere near the heart of the city. I don't know what the price difference is by renting at the airport, but I would be willing to pay 10% or even 20% more to avoid driving downtown. Remember, ZTL violations are 80 Euro a pop. If you weren't careful, you could easily negate any savings just in fines.

We were there in December. Late June will be even more congested.

you'll also have to be vigilant to avoid the automated speed cameras, as they don't usually give much / any leeway.

There is a 5% leeway with a minimum of 5 Kms per hour.

dlynch56, a couple of ZTL signs in Florence:
http://imobi.fi.it/media/ztl.png
http://it.apartmentsflorence.it/img/e907c9bfbf7d80c5ecfdaca74569f3c2edc4e49d92853b3ab436649201ff4b70.jpg
In Florence also bus lanes are camera controlled:
http://www.mobilitypress.it/wp-content/uploads/2014/08/corsie-preferenziali-631x434.jpg

If you are afraid to drive anywhere near the ZTL (Limited Traffic Zone), you should at least return the cat at an out of city center location. Exiting the ZTL from Borgo Ognissanti is not a problem as the cameras are only at entrance points. From Borgo Ognissanti (which is a one way street going west) just go west all the way to Piazzale di Porta Al Prato (big ancient City Gate with tower). Once there you are out of the historical center.
Return your car at the following locations:
HERTZ Via Del Sansovino 53
EUROPCAR Via Forlanini 2

The above locations are far from the ZTL and near the freeway and being not at the airport, are cheaper if you pick up there than the airport. If you use the consolidators I recommended above, picking up at the airport is generally no more than $30 for a two week period. However the airport is farther out and by choosing the above locations you are still close to the freeway entrance and save on taxi fare to get there too.