Around my area (this region in North Texas) it is understood that if a device or object is left at the curb a day or two before trash day, that it is free for the taking. And if you put a note that says "free" on it, all the better. Perhaps someone else will take it off your hands and recycle or reuse or re-sell the old microwave?

You can sell things on eBay for "local pickup only." And I'm hearing ads these days about a new phone ap called "Five Miles." I just looked it up: https://www.5milesapp.com/. Craig's List is an asylum run by inmates. I rarely look at the site any more.