For one elevator I might look at mounting an AP in the top of the shaft (maybe with a panel antenna?) and using the MV12 on a wireless link... But I'm totally thinking out loud here and I have no idea how well that would work.
@lfischer-gcpl I don't think you'd have an issue with the distance limitation then. You'd need to get CAT6 run along with the power/control cables in the shaft and then you'll have CAT6 at the car to mount the camera inside.
Wireless is also another good idea from @jdsilva but isn't available in MV12's firmware just yet.