Hi Wendy-

I can give you some pointers to help get started. Note that I haven't done it this way so there might be details I'm missing. Key elements are Workflow's activity of Set Records Management Properties along with records management search options in the desktop or web client.

Assuming you have the date of hire on the employee's folder or can get it there (WF with lookup), you could:

1. Create a retention schedule of 4 Years Then Destruction and a cutoff instruction of Hired (at least as an Event type, but ideally something like event + monthly)
2. Use Workflow to loop through all the folders and assign the cutoff instruction and 4 year retention schedule to them
3. As part of this same loop logic (I think), set the Event Date as the date of hire
4. Once that's all set, you can run a search (in WF or manually) for all of the folders that are eligible to be cut off (Due for Cutoff before today). Watch out, this makes things read-only so you won't be able to add records to those folders.
5. Finally, for things that are old enough to be destroyed, you can run a Disposition search for items currently eligible for destruction. This destruction must be done manually; WF won't do it as part of its RM activity.