Brattleboro kids do a great job with Halloween. Impressive amounts of creative work go into choosing and making costumes. Maybe adults in town can up the ante with a bit more Halloween prop making.
YouTube is filled with videos on makeup, costumes, haunted mansions and so forth. I’ve chosen this one as it gives a good overview of some easy tombstones, which seem essential for any Halloween haunted graveyard.
In general, there is a lot that can be done with carved foam blocks and paint. Once you get this down you might want to move on to videos about spider webs, hanging bodies, rain effects, or lighting tricks.
May your mansion be haunted by many friendly ghosts.