The bugger is that they're taking ONLY the valuables, and they're obviously picking and choosing and looking through our things, now that they've seen the layout.

Mom and I are going to buy a motion-activated flood lamp and going through the pawn shops either tonight or tomorrow, but I want to put a dead stop to this before they get bolder break into the house when we're gone. (Dad sleeps in the living room every night, and Hell knows no fury like dad when he's rudely awaken at 4 A.M.!)
The problem here is I want to put a blanket of energy, a ward, or just some type of shield on our carport, with intent along the lines of "If you move anything off this property without explicit permission, may the fury of Mother Earth rain down upon your head until you return what has been taken!".
Is this necessarily bad? I'm pretty sure I'm going to go through with this, but I want to write and conjure something strong enough to ward off the would-be thieves or at least make them a bit miserable until they return what was taken. (Legal involvement is not definite just yet.) Even if we don't get our things back, I'd feel better if the slimeball that took our things suffered just a little for it. To me, theft is an unnacceptable crime that is only appropriate if there's something other than money as a reason for it. (Someone stealing to feed themselves, for example.)