The most important thing to think when looking where to set out your boxes is where is the food, food means in my area mostly mice voles moles and chipmunks. So i look for old rock walls, take apart a couple of the rocks and place the box uneath them to prevent a coon from tipping it over i also wire the bait, wich should be as bloody and fresh as possible, to the back of the box and bed a #0 or #1.5 coil spring of jump trap in front of the box, also areas with hollowed out fallen trees are good, same with old barns.
good luck
-cory