There's a decent article by Time Out that describes some of the better known shopping streets in Florence. https://www.timeout.com/florence/things-to-do/best-shopping-in-florence
I've bought a few leather goods over the years. There's leather, and then there's good leather. Like anything, you need to know what it is you are buying. I had a pair of Italian loafers from Florence that lasted for many years of hard city walking. Although... DH had a really hard time dragging me away from the Ferragamo shop before I spent next years travel budget. And the gorgeous crimson cross body bag I got from I Medici 7 years ago is till as good as the day I bought it, despite using it every year as my "winter" purse.
I haven't bought gold there, finding it overpriced, but there is lots of costume jewelery to be had. I once bought a lovely hand made blank book which I used as a travel journal - there are a few good paper ships in Floremce, although not as plentiful as in Venice.
Basically I have an idea of how much I want to spend and just window shop until I find what I'm looking for.