By default, proposals display all items in the package.
If you want to hide the items in the packages in the proposal, you can do so. To change this setting, go to the Edit view of the Products section.
Set the "Summarize package" option to ON. The items in the package will now be hidden.
If you don't want to show the package price and only the price of the items, set the "Summarize package" and "Show package price" options to OFF.
