I'm quite surprised this is not an option, but when you load a Sales Document and have shared it, you can't go back later and replace it (say your content changed slightly) so you have to create a whole new document and lose your sharing data.
Please add the functionality from Marketing Files - "Replace" to allow the file to be updated as changes are made.
Or better yet, allow for the Sales Document to tie into the File Manager so if marketing updates a file, it would update for sales automatically. Similar to how a CTA auto-updates when the file is connected from File Manager.
This very basic issue is solved by the CloudFiles app. You can not only upload trackable files in your deal/contact/company page, you can also replace them anytime, preserving the old link and analytics. CloudFiles enhances HubSpot Documents and solves many of the issues reported here on the community.