We ended up putting steel poles with a T bar, in concrete embedded with river rock. DH is serious about feeding his birds I wire up whatever feeder we hang, otherwise it gets dragged into the woods, never to be found. I also have a squirrel baffle under each feeder, which is a stepping stone for the coons. We tried the shepherd's hooks, the coons just bent them to the ground. And the possums have joined them.
This is the one we use (the green one)
If they can shimmy up the post they can't get to the food.
It also comes this way ..
We have 4 feeders ... 1 in a tree the other 3 on shepherd hooks.
They liked climbing the pole on one of them so I searched and found a simple solution.
Bought a slinky. Attached it to the top of the post and let it hang down .. they could no longer get up but had a real fun ride
I don't have any kind of anything at the bottom.
We also have raccoons and possums but they don't make it up the posts so they settle for the stuff on the ground.
Have you looked at youtube at some of the contraptions people have made ... you will LOL
Now there is a feeder that spins when a squirrel gets on it as well as one where it closes .. both work based on the weight of the animal.
Good luck .. I know it's a challenge !