We (based in Europe) use https://quaderno.io/ https://quaderno.io/ for the tax calculation, reporting, invoice creating and sending. For example they collect th

We (based in Europe) use https://quaderno.io/ https://quaderno.io/ for the tax calculation, reporting, invoice creating and sending. For example they collect the proofs the EU needs, like country of user, country of bank, country of transaction (IP address). They're not a payment provider but connect to others, we use Stripe. I recommend them. Not sure about US states, that doesn't apply to us.