How well do you know your community? Do you know if it's primarily singles or families? Or maybe it's an aging community.
Knowing your market is essential to designing your haunted house. A Mike Meyers Halloween will play well to your young adults but will be given a wide berth by both your young families and your older folk. And planning a loud haunted house next to a nursing home would be, as they say, a Bad Idea. So the first thing you need to do is to figure out your target audience.
The first thing you need to do is figure out how wide your range is going to be. If you're setting up a professional house with a large advertising budget, your target audience will be drawn from a large geographic area. Those kinds of haunted houses need to promise and deliver huge thrills to get the people to visit and return. In fact, that type of haunted house would do well to have variances in the scenarios so as to provide something new on every visit.
But for the most part, your house is likely to be a local affair, and the first thing to do is consider the demographics of your location. If it's kid-centric, with lots of playgrounds and parents with strollers, you'll probably want to design a house for the younger set, with storytelling and minor scares rather than the heavy-duty thrills. If it's teens in the area, you can go a bit stronger. And if you're in the neighborhood of a university or community college, you've hit a sweet spot— both your workers and your guests are likely to come from the college.
The next thing to take into account is the local interests. See what clubs and organizations are popular in the area. A local history club can be a great source of inspiration. Local "ghosts," complete with accurate historical personalities, will add a unique flavor to the proceedings. Or perhaps your area is big on football. Why not have a haunted team?
The most important thing is, of course, to get the community on your side. Don't set your house in a heavily residential area and be loud late into the night. Make sure to provide safe areas outside your house. And figure out concessions you can make if people will be upset with you— it is not done to be the neighborhood bogeyman, even if you have a bogeyman in your house.
Next up: Themes