I am in Florida too! Just north of Naples, Florida in Estero.
All I could find on Squarespace is a post from 7 mos. ago here.
As for the sales tax, it is best to research that topic on FL Dept. of Revenue site. It can get complicated, so it is best to be sure you have it set up right in qbo. You can get some good info on that here. I like to recommend to my customers that they explore the app Avalara. It is great when dealing with different states and Florida taxes. They have a wonderful blog too. They are a wealth of information on all sales tax. That page in particular is a good reference for finding out the rates.
The above references are a place to start with your new business. :cathappy: