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Navigate to the offer/invoice preferences in the Setup & Settings section on the Overview tab or use the App Launcher browse for "Preferences" and open the active record:
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First of all, you have the option to turn the first page - the cover letter off altogether. To do so please un-check "Show Cover Letter".
Your next option is to remove the info box on the cover letter. To do so please check "Hide Info Table on Cover Letter".
If you like the information box you can configure the 7 variables on the right by choosing a field on the media campaign. The fields and their labels get are displayed in the order from top to bottom as selected here.
If you are using layout for your legal entities you can configure this in all records differently if needed.
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