The problem with LT investigation other houses and haunted places is that it would TOO similar to the Wyandot Estate. They can only do so many "haunted houses"
It could work if they tweak enough to where it's fresh. Take my "Civil War" suggestion for example. Use the story of a plantation home being the site of one of the most gruesome battles in Civil War history. You would go thru some of the rooms of the home, but also through some of the fields. Imagine the last scene being a battle between the 2 ghost sides. Other roads they can take, maybe an actual demon house, like Drag Me to Hell type stuff without the cheese. Have it haunting a hotel or something. It doesn't just have to be paranormal though, it could be cryptozoologic investigations. Mothman house anyone?