So I found this bike in the trash not too long ago, and besides being wrapped in all kinds of vines the only issue it really had was the seat tube was rusted in place. Those of you who have experience with bikes probably understand what a pain it is to unstuck a seized seat post.
Its been a whole process heating it, spraying it with WD-40, letting it cool, then heating it again. Doing that repeatedly on and off over the course of two days, and it finally came out. I used a heat gun, but I saw a British guy use a tea kettle of boiling water to unstuck his, so that's an option too I guess. Then clamped it in the shop vice and used the leverage of the frame to twist it out.

This hobby is honestly just for fun. These rust bucket bikes I find in the trash don't really bring in much even in working condition. I often end up giving them away.