If you ever published an ebook or just looked into publishing an ebook, one of the biggest costs is the cover. I’ve seen prices as low as $40 and as high as $300+. You could make your own ebook cover, especially if you’re a graphic designer, but most people don’t have that skill.
Luckily, there is this great place called Fiverr, where you can get all kinds of stuff starting at $5. I got my last ebook cover from a seller named Angie. Check out here gig. She does terrific work. Also, check out everything that Fiverr have to offer.