If you are not familiar with VMWare Flings, then you should rush over and start checking them out NOW!!   If you are familiar, then maybe you also noticed that the engineers over at VMWare just released a vCenter to VCSA converter!!    There are a few limitations:  Must be vCenter 5.5, must be using a separate SQL server, downtime required and a few others. I have not had a chance to try it out in the lab, but I hope to soon and post my experience.