If you really think you'll have some bears around, the simplest thing is a battery powered electric fence. Have used ones that run off a car battery, and some that use a couple d-batteries. The d-batteries are enough, works for both species of bears, they don't seem to like electricity and it doesn't take much of a shock to deter them. Use them around camp when don't have to pack things far, & around my bee hives. Look in the ag supply places, ~$100-$150 for all the pieces/parts, there are also some kits where the pieces are in a nice bag for transport. Make sure you get a good grounding, and run a couple wires at different heights (don't want to let the cubs in & separate them from momma). As you said, usually more concerned about coming back to a mess than showing up when I'm around.