Below is a video of my core construction and test. I had a reindeer motor, wire, scrap aluminum metal, scrap wood I connected with L brackets, a bolt, nut, and a washer. I then had some scrap wood baseboard sitting around that I attached to a door hinge I had on hand.
The last video is a test of the setup once I put the skeletal zombie onto the baseboard. The prop had pvc pipe so I just screwed it securely to the baseboard. I picked that static prop up from a store a couple days after Halloween for $7. I just placed it behind a box so you get the concept, I will have it in the yard peeking out from something on Halloween night.