The problem is what you're looking for is far less common than it used to be.
The bottom has dropped out of the market. Cars under a certain value are usually scrapped and/or parted out. You will find them occasionally but it's getting rare. In my local area I find that Craigslist has the best selection of beaters, but it's still difficult to find anything worthwhile under $4000.
Might be time to consider a motorcycle, scooter, or e-bike of you can make it work
Edit: one more thing. There are ways to browse FB marketplace without an account.
Just gonna guess, is this Eric Dubey?