The source for kits definitely makes a difference. I don't buy a lot of them - large stash and don't want look alike quilts - but once in a while something catches my eye and I really do want it to be JUST like that one.
I have found those from Fat Quarter Shop to be pretty generous.
Some designers and shops offer "oopsie" bundles in case of cutting error. Of course, that's more $, and hard to justify a bunch of FQs if you make an error cutting one. If you make it when the kit comes out, I'd pass on those and, if you do need more of something, look online for whatever you are short of. If it has languished in your stash, you'll have to find something to substitute.
A very well known fabric designer does a BOM for every line she comes out with, shipping them from her own business. In 2024, several of us found ourselves short of one of the fabrics for the 3rd (I think) month. She was quite short with her response, saying it was impossible. It really turned me off, but I still love her fabrics. Enough so that I've signed up for another next year.
Long ago, I found out the hard way that you should always cut the largest piece first, regardless of whether or not that is "Piece A" or "Piece F" of a given fabric. I'd always cut them in order, and that doesn't always work. You can get those smaller pieces from scraps of what you have, but not so much getting the large ones from leftover strips!