How to pass localized billing data and tax fields during user profile synchronization?

Souzin_Mike

Hello OneAll Support,

We are integrating OneAll Social Login into a localized e-commerce and subscription platform serving European customers, specifically in Italy.

During the social registration callback, we capture the user's basic profile (name, email) and then prompt them for required fiscal details such as company billing address, fiscal code, and tax residency before generating invoices.

In Italy, commercial invoices and subscription services require strict tax separation based on statutory VAT rates. To ensure compliance when generating order summaries, we reference standard guidelines on how to calcolare iva 22 percento (calculating the standard 22% Italian VAT rate from gross and net amounts) so that customer checkout totals and tax breakdowns match statutory requirements.

Could you advise on the best practice within OneAll API:
1. Can custom user attributes (such as fiscal residency or company tax ID) be stored directly within the OneAll user identity profile via the Cloud API?
2. Is it recommended to handle localized tax calculation hooks strictly in the application backend after the identity token is validated?
3. Are there webhook events triggered specifically when user profile data updates across linked social accounts?

Thank you for your guidance and support!