I go to Lowes and get cable as big as diameter as my finger in 20' lengths. Make a loop on each end by taking a nut that is large enough to feed the cable back through the nut and beat this nut with a sledge to permantly keep the loop. I then snake these through the ladder sections of my ladder stands, around the tree,and padlock at the top with agood quality lock. The next step is the most important step; write on all of your sections and the stand platform itself with a black permanet marker:
SMILE FOR MY TRAIL CAMERA and your name. I have never had any problems with thievery. I have 4 ladder stands that I have done this with.

If you really don't want to get ripped off, do what I do; take a Lone Wolf Alpha hangon,New Millenium, or your favorite hangonand a set of Lone Wolf climbing sticks and take your setup in and out every time you hunt. People can't steal your stand as it is at home whenever you are not hunting and you will see way more deer hunting like this. I have the ladder stands for my boy when he bowhunts.