Surviving Renovation

Kate Winslow inherited her great-aunt's Victorian house in Adams, Tennessee. She leaves her job on Music Row in Nashville to turn the old house into a bed & breakfast.
Kate reunites with her childhood best friend (& first love) Will Bell, who decides to partner with her in renovating the house. Almost immediately strange things begin to occur, and Kate and Will suffer multiple injuries. Some suggest that the Bell Witch is at fault.
Beginning in 1817, supernatural happenings bedeviled the Bell family subsiding only after the death of the Bell patriarch John Bell, Sr. The Bell Witch is the name given to that evil spirit that disturbed Adams, Tennessee. In 1819, Andrew Jackson spent a night at the Bells' (as many apparently did) to witness the acts of the spirit. At the end of the night, he is quoted as saying, "I would rather fight the British at New Orleans than fight the Bell Witch."
Who is at fault for the strange happenings at Kate's Bed and Breakfast?
What mysteries does the old house have to share?
Are the strange happenings a figment of Kate's imagination?