I few years ago, I wrote a book rather abruptly...if one can actually do that. It does need to be rewritten but it draws money every month. I have it on Amazon and a few other places. This book tends to make more money around the holidays. I don't promote it at all. I probably should. I get paid two months in arrears so this month (Jan), I will get November's royalties. See attachment. It continues to make money because I leave it up there. If I take it down, it won't. :-)
https://www.amazon.com/How-Not-Be-Asshole-century/dp/0692707298/ref=sr_1_1?crid=XRMIBSL6S0BH&keywords=how+not+to+be+an+asshole&qid=1674680648&sprefix=how+not+to+be+an+asshole%2Caps%2C89&sr=8-1