EU Requirements

For EU especially German/Austrian market we need
an invoice mail with PDFs attached for terms and conditions, power of revocation and additional policies (it has to be sent to the client to be valid, a link is not enough!)
proper wording of the buy button in German (e.g. Kostenpflichtig bestellen)
a checkmark for privacy policy and general terms and conditions
the buy button MUST be directly(!) next to the final price
all costs including shipping and VAT must be visible
per item cost must be visible
a field for VAT number must be included in the checkout process for B2B especially if the product is meant for a recipient in another EU country as the seller
if VAT number is supplied and the recipient is in another EU country the tax is not applied and a note on the invoice must state reverse charge
* VAT check. An API is available - see https://viesapi.eu/docs/