For most self-published authors like myself, I priced the book based on a consideration of two things 1. What I think it's worth and 2. What I think I deserve per sale for the effort put in... I worked on my book for 4 years... it's over 300 pages... and it's damn good. That's my opinion, but also the opinion of over 200 reviews at this point.
I wanted to make around $4 per book sold, whether it's a kindle purchase or paperback... which led the kindle to be $8 usd, and the paperback to be $15 (overhead for print on deman is rather high).
Anyway, check the book out if your curious... I think you'll find it very worth your $$$.
https://www.amazon.com/Not-That-Anyone-Asked-Finding-ebook/dp/B08LG5V4X4