Cashier/Stripe help

Hi All. I am struggling with Cashier and Stripe (still). There really doesn't seem to be any decent reference on the latest and greatest... everything is Laravel 7 or older.... The Laravel docs tell you how to do specific things, but not what things you NEED to do and in what order. My current issue, is that I am trying to setup a subscription, that I had working in laravel 8 and cashier (something older than current) and when I tripped on stuff I decided it was time to go to Laravel 9 for this project and hence the latest cashier.

Now when I do a user()->newSubscription(....) it fails because my customer location isn't recognised by the tax engine. I get the theory behind the tax engine and why its there, but I don't understand how I am meant to structure this stuff. I am selling a SaaS offering, and I have peoples email address and timezone.... so I can get a country... but I dont want to have to get a users state and city etc just to make stripe work....... If anyone has any cheat sheets on how to do all of this the correct way I would love to read it.... alternatively, if Laracasts could redo their courses in cashier using V13.11 of cashier......

Thanks in advance clever people.