The Haunting of Elmwood Manor

Pekin Dewlap is a 15-year old high school student fascinated by ghosts. It's been three years since she last saw one, but she firmly believes that with a little effort her ability will return. That effort turns out to be starting a ghostbuster business with her two best friends, Amber and Scout.
Their first customer hires the three teens to remove a ghost from a hundred-year-old mansion. No one has lived in the old house for decades because the ghost scares them away.
The kids are able to entice the ghost of Miranda Talbert to show herself through creatively appealing to her loneliness, and in no time the three teens and the ghost are friends. Until the kids confess they want to release her from the dilapidated old house.
But they need Miranda to tell them what happened to her a century ago. Miranda insists she can't tell them and cowers in fear of something evil that shares the house with her.
In order to help her go into the light, Pekin, Amber and Scout must solve the mystery of her disappearance and save Miranda from whatever is haunting her. Before that entity can add Pekin to the ghosts who haunt Elmwood Manor.