Starting a Horror/Haunting Novel

With NICE GIRLS DON'T BITE making the rounds of agents, I wanted to start another novel right away. Amanda Hocking recently interviewed me in her blog, one of her questions being what monster I feared when I was young. In the process of answering I mentioned that our house had a ghost who was not frightening. That house, its rural location, and that ghost had been perking in the back of my brain for some time. I determined to write a horror/haunting novel. The location descriptions would be easy because I had lived in that weathered two-story frame house for seven years. It had a ghost whom I saw often and named Oscar, but he was benign and occupied himself by walking from room to room and staring out windows. What did cause a little frisson of spookiness, however, was the name of the previous owners of the property. The family's last name was Sleeper. I would title my novel SLEEPER, it would take place in that old remote frame house, and it would have three malevolent ghosts rising from a bloody incident 70 years previous. I was excited by the idea and began by creating a 14-page, single-spaced outline. The outline is my way of knowing if my concept has meat on its bones and if I have enough arc to arrive at a satisfactory conclusion. It's something like the way The Man I Married first builds a fully-detailed scale model before he begins construction of a stage set. Thanks for reading. Joan Sween.