Florence parking

No specific advice, but be aware that most of Florence is ZTL zones, so you need to park well outside the zones, or take a designated route to official parking. No driving to your apartment/room, unloading, and then finding parking. I would contact your rental (or hotel if that applies) and get their input. Otherwise, take a look here for more info: https://florence-on-line.com/travel-tips/maps/florence-driving-map-ztl.html (Note, this came up for a random search on "Florence ZTL zones", there may be better sources of information)

You’ll need to park well outside ZTLs

Search results for “Parking in Florence “
https://search.ricksteves.com/?button=&date_range=2y&filter=Travel+Forum&query=Parking+in+Florence+&utf8=✓

Katy, looking back at previous posts, it's not completely clear what your itinerary is. Given the cost of car rental - and that you definitely do not need or want a vehicle in Florence and Venice - do you really need to keep one that you won't be using for your time in the city? Is it possible to simply rent one for the day(s) you'd be exploring the Tuscan countryside?]

ZTLs are a factor in Siena as well. Have you planned for where you'll be allowed to park there?

First of all check if, depending on your itinerary, makes sense to rent the car only after you leave Florence.
In any case these two underground parking lots are outside the ZTL and are closest to the Santa Croce area:
1. https://goo.gl/maps/F4rZqprn5cQnsJeX9
2. https://goo.gl/maps/c1eAj3hy4SvQWCW26

There are also more private garages inside the ZTL, but they would be more expensive and they would need to place your license plate number in the City White List to prevent a fine to be issued to you.
Below is one such example:
https://goo.gl/maps/Sni7pHdgDCnwYCia9

Thank you for everyone's suggestions. I will look at the garages nearby.
I have not looked at the ZTL for Sienna. Suggestions where to park? Are there ZTLs for Lucca or Volterra or San Gimi and parking suggestions for these areas?

Thank you

Kathy

Are there ZTLs for Lucca or Volterra or San Gimi and parking suggestions for these areas?

Without looking up information for each, you can pretty much bet that nearly every municipality in Tuscany and the surrounding areas have ZTLs. Pretty much plan on approaching each town on main roads, and look for parking lot signs on the outer areas of towns, and park. Google maps can indicate parking lots as well.

If you are not familiar with ZTLs, they automatically ticket you when you enter into the area...and each time you enter into another one...even multiple times in a day. You will not receive notice of the violation, until your rental company charges you a fee to send the authorities your info, then you get tickets months later in the mail. A single ticket will run you several hundred euro.

Katydoc-

Please read up on driving in Italy
ZTLs, parking, speed cameras, tolls

Would hate for you to come home to multiple tickets costing big bucks!

This is old but still helpful

http://driventoit.blogspot.com/2015/01/driving-in-italy-including-dreaded-ztls.html?m=1

All drivers must have an IDP-International Driving Permit which you can get at your local AAA

Not sure where you are coming from or why you’ll have car in Florence?
Maybe we can help you save some stress and $$ if you share your itinerary