This might be a controversial one, but there are lots of businesses and sites out there that would love a link on Wikipedia, and it is not that hard to get one with a bit of know how and work. However, not many people have the knowledge or the time to do this and would be happy to outsource. You could advertise this service on sites such as Upwork.
My 10-year-old son brought home a book from our park’s free library box. It was a biology textbook – teachers edition. He said it looked interesting and hey, it was free (having no idea you could sell it). I scanned it in my Amazon seller app and realized it was worth around $150. He was so excited. We listed it for sale for $130 and it sold! Going to tell him, he just made $130!