Deleting the amount of an invoice when it is linked to an object

Hi,

When an invoice is linked to an object (for example an activity), when it changes status, a notification email is sent. The default email format displays related items and in the case of an invoice, it displays the amount at the end of the line (xxx.xx). However, the recipients do not necessarily have to know this value. How can we delete this information?

I know there is the email template module, but the result is clearly less beautiful.

Thanks for your help.