yes you can, and 2 dedicated cards would be a good policy - you may find that you will save money with a monthly cell plan though running it only during hunting season , the gas and drive time alone unless you live on the property ends up costing more than 1 $15 plan on a network.
you can pull the cards, just use the same card in the home camera or at least clear them after you view the pics on them- dont swap cards from home to home unless you clear them
you can run it the way you want but you will need a camera set as a "home" on each property- any camera can be set as a home unit when running them without cell service - you wont be able to access some features or make remote adjustments to the cameras without cell service but you may not need...
you an switch back and forth from Verizon to ATT in device details , edit and then you will see the box to mark for attt or Verizon, it sounds like its something else in this instance though, if you are 99%
if you disable the camera it will turn it into a repeater - to go in and out of the simple menu , power off the camera then hold down the more button for 5 seconds and it will prompt you to enter either advanced or simple menu
you would need to arm it and have an active plan to determine which is best using the L home, if you want to move your current plan to the new L home unit you would need to call CS at cuddeback
go to camp- then device details then edit , and you will then see the option to choose att or verizon, L series have both Sim cards and better coverage than the G