Is it possible to power up a camera with no network, have it record to the SD card? I have a commercial customer with an unoccupied building that keeps getting the trash can messed with. He just wants to pop something up, no internet, no network. He is fine with pulling out the SD card as needed. Possible?

I know that you are the "AV" guy but there are services/companies out there that already do this as their sole business that cater directly to construction firms. Don't cobble together some contraption that isn't really designed to do this.

I work on commercial sites where they have RF cameras that are either mounted to poles that are cemented into 5 gallon buckets or they have magnet bases that they can just stick on to steel beams around the site. The cameras broadcast back to a recorder in their construction office and then out to the internet. The builder can just bring the system and cameras along to their next site and just throw the cameras out wherever they want.

Yes, you can.  If you throw a cheap wifi router in they can check on site without pulling the card.  It would be a pita to go and pull the card.

EXCELLENT suggestion. Thank you sir.

All the IP cameras we use have a 12V and network connection on them and can be powered either 12V or PoE. What you are asking is possible, however you would require 120VAC close to the camera to plug a 12VDC power supply into it. You would obviously want this high enough so that it can't become unplugged.