Restricting edit on approved items after approval

Scenario:
I got this question again , on how to ensure a form / document is locked after it has been approved. ( After some sort of workflow is done ).

Solution:
One of the solution is to declare the item as a record. This can be done in many ways but easiest no code solution is using 'SharePoint Designer Workflow'. As it support an activity to declare an item as record as shown.



Note : You can define record declaration settings at the top-level site in your site collection. Record declaration settings govern how records are treated, such as whether they can be edited or deleted, what metadata is applied to the record, and what a record’s retention policy is. Record declaration settings specify restrictions that should apply after an item is declared as a record, user roles allowed to declare records and if record declaration is available to all site users.

Steps:
Step 1 : Ensure Site Collection level feature 'In-place record management' is activated.

Step 2 : Navigate to site collection settings and check for 'Record Setting' link.



Step 3 : Here's default settings , but you can opt for the one you want and save.

Step 4 : Once In-place record management is enabled @ root level , you can navigate to list/library setting to modify it @ list/library level.