Hook before generating an invoice

[GiovanniS]

Hi,

I need to change the "tax Exempt" field of a client before the invoice creation.

I can successfully change the field using the invoice creation hook but the invoice is provided with no modification.

 

I'm not sure to use the right hook!

Best regards.

 

 

[Kian]

Why don't you simply enable/disable the Tax Exempt status of the client in question? This way WHMCS will generate invoices accordingly with or without VAT.