Good questions! I used apples and peanut butter on my last setup and the raccoons and possums loved it

. Deer not so much

I heard of cob (corn, oats, and barley) working at times. Oh, I did put out some stump licker and I have had a doe hit that a few times. I will keep trying to see what works best. Keep me posted on your setup.
I have heard the store bought apples will not work compared to wild/fresh of the tree apples. When the apples start dropping I will change my setup.