I have a list with two content-types. I only want the user to be able to edit or delete listitems created from only one of the content types in SharePoint 2013.
I never did that myself, but I think you can use SharePoint ItemEventReceiver – ItemDeleting to deny delete of that kind of documents.
Sample of SharePoint Item Deleting Event Receiver Deny DeleteÂ
Hope it gets you to right direction.