book where a private investigator/writer accidentally rents a haunted house?

it was multimedia, like fictional compiled letters, emails and newspaper articles. some other stuff. centered around a private investigator (or writer??) struggling to find business, ends up renting this dreary old house next to a cemetery for like inspiration or something?? theres a cat that wont leave iirc. there was a ghost (pretty sure her name was olive) who had written novels when she was alive??? this is driving me crazy omg