lock your cars up

snip.... Reminds me of a sign:

"These premises guarded by trained attack dogs and armed guards 3 nights a week. You get to guess which 3 nights"
Which reminds me of a story of a friend of my grandad's. Couldn't get the local LEO's to pay much attention to the petty thievery going on around his place so he put up a sign on his shop (he rebuilt starters & generators) that read: "Caution: Set-Gun. Do Not open door." One of the deputies saw it and told him to take the gun down, that was illegal. The deputy was handed the keys to the door a told to "go ahead".

Wouldn't have helped in this case, but in the past I've used one of the Hella battery switches with the removable key to disable battery power as a theft deterrent.