Georgia has 970 sales tax regions. I was shocked to discover I'd have to manually enter those, all of them, to open my store here. This seems like such a basic feature that I didn't discover I'd have to do this until just after the 14 day refund window closed. It was literally the last thing we had to do before going live.
We ended up postponing the opening a week and moving the store to one of the several competitors that offer automated sales tax calculation. I closed the account here and just had to eat the full year I pre-payed of the highest tier here. And considering the time I would have had to spend entering and proofreading 1000 tax rates, I think I still came out ahead.
Still, I'm shocked. Never in a million years would I have guessed SquareSpace, who I considered to be the leader in this sort of thing, would make me do this.