Marieke Hardy's book from mid to late last year is now US $3.84 on the Kindle store. On Booko, cheapest eBook price is $17, and cheapest hard copy price is $27.
EDIT: Changed Amazon URL to Desktop version
EDIT 2: Also available on Google Play Books for AU$3.63 - https://play.google.com/store/books/details/Marieke_Hardy_Yo…
What's the normal price at the Kindle store?