Back in the day you you didn't have to pay if you ran a Google Ads campaign. There was no minimum spend. If you ran a monthly AdWords campaign for $1/mo you got free GA no matter what your traffic level was.
The main catch is that GA goes to "sampling mode" once your traffic gets high enough, and I think you have to pay extra to get full datasets.
I at the time found some prices online searching around but nothing from them.
We were very hopeful we'd get some sort of discount because we're in educational tech, so our income per user is very low, but nope. Free to $100k overnight is insane. We’ve got a guy whose full time job now is basically developing analytics tools for us and it’s a cheaper solution.