I couldn't find any up2date information.
As UE merchant I need to collect VAT and other fiscal data from all my customers, in order to invoice them properly.
Can you tell me how this issue is solved in spotify?
Doasn't really matter if the custom field is per order or per customer.
Basically we need to collect, per each sale (or customer):
VAT for organization and Personal ID (in Italy we call the Personal Id "Codice fiscale").
So we need kind of custom field, that should be mandatory to be filled up by the customer per each sale.