What type of user does the Salesforce sync user need to be?

The primary Salesforce sync user should have the standard system administrator profile and our full permission set wherever possible. This will ensure that the sync can run without any permission errors. If you need to use another Salesforce profile, please ensure they have our full permission set. You may still see errors should the profile lack Salesforce system permissions. It is worth noting Salesforce can be very vague, and the error message won't give you the exact permission that is missing.  In short, if you can use a system administrator profile, it will make the whole process very robust.