Best argument/justification for PDM.

We have three seats of SW and three users. We are storing all of our files (>3000) on a server and accessing them with Windows File Explorer.

How much easier would our lives become if we transitioned to PDM? (Sorry, I'm an engineer...I can't help it. )

We need to justify the cost. 

SolidworksSolidworks Pdm/enterprise Pdm