I will probably pick up an NVR for the time being, just to get something up and running but the cameras also have SD slots which will allow for a few days of footage at least in the event my system fails. I was looking for something more akin to EagleEye, where a bridge would be installed to upload the footage to a server but instead of using someone else's, I would use mine. The site-to-site VPN sounds promising, I'm just still unsure of what VMS could be used.