Permission settings to make a "comment box" style list for users, using only default permission levels

Question

I'm a new SharePoint SCA/developer in a large organization with very locked-down access to a SharePoint Server 2016 site collection. In general, from an admin point of view, we aim to keep permissions as out-of-the-box as possible for ease of support later.

I have a site administrator who is requesting custom permission levels for their site in order to create a "comment box" style feature that will allow users to add items to a list, but not modify or delete the items they have added. The users should otherwise only have Read access to the rest of the site.

Is there a way to do this using the Default Permission Levels Microsoft lays out?

If no, my thinking is to create a new permission level with a descriptive name like "One-Way Contribute" to act as a red flag for future support needs, and then just duplicate the default Contribute permission level while removing "Edit Items" and "Delete Items" from it. I would love to avoid this and stick with the defaults if possible.

Answer 1

You can create your own custom permission level and assign it to the user.

• Go to Site Actions > Site Permissions > Permissions Level > Add a Permission Level
• Select Add Items,View Items ,View Versions and leave the rest of permission levels checked as it is by default.
• Determine if a custom SharePoint Group needs to be created or not. If you are planning to give this permission to many users , you can create a SharePoint group and add users in that group.
• Give read permission to that group at a site level.
• Go to the library > Click on the tab named Library on the ribbon. > Permissions for this Library > Stop Inheriting Permissions
• Go to grant permissions > select the user or SharePoint group that you need to give permission to. Scroll down way to the bottom of the page and you will find your newly created permission level appear there. Select that permission level and save the form.
• Now it should work. Test it