Clouds Over Stormcrest — J.H. Rhodes

Ever since she was a little girl, Dana Hanson had been fascinated by Stormcrest, the haughty old mansion that stood near the edge of a cliff, inaccessible and mysterious. When the wealthy Carmichael family moved into the empty house, and Dana was hired to catalogue their exquisite art objects, she was delighted. Then Dana's delight changed to terror as she discovered the malignant presence at Stormcrest that was out to harm the Carmichaels and her, as well. Worse yet, at times almost everyone connected with the place seemed capable of doing evil, even handsome young Phillip Carmichael and his magnetic cousin, Bill, the two most appealing or sinister men Dana had ever met. Was one of them destined to destroy her?"