Just finished Disappearance at Devil's Rock by Paul Tremblay. I read this on recommendation from Sai King and was not let down. Creepy, sad, well-written.
The Kindle edition is still only $1.99 at Amazon.
https://www.amazon.com/gp/aw/d/B015MO7OGQ/ref=mp_s_a_1_1?ie=UTF8&qid=1498242107&sr=8-1&pi=AC_SX236_SY340_QL65&keywords=disappearance+at+devil%27s+rock
The Kindle edition is still only $1.99 at Amazon.
https://www.amazon.com/gp/aw/d/B015MO7OGQ/ref=mp_s_a_1_1?ie=UTF8&qid=1498242107&sr=8-1&pi=AC_SX236_SY340_QL65&keywords=disappearance+at+devil%27s+rock