The house used in this episode is the house Fox Mulder lived in during the last two seasons of The X-Files show.
The Stillwater farmhouse is the Blieberger Farm, a private farm in Langley, British Columbia. A popular CW Network filming location. This same farm house was Zelena's farm in the TV series Once Upon A Time. Blieberger Farm has also doubled as locations for other productions: The hideout for a nest of vampires in the Supernatural episode "Bloodlust" (an episode which features Once Upon a Time guest star Ty Olsson) and the house of murder victims in Lincoln, Nebraska in Supernatural episode "The Magnificent Seven" (an episode which features Once Upon a Time guest star C. Ernst Harth and Once Upon a Time in Wonderland guest star Ben Cotton). The Deacon Walker Farms in the Psych episode "65 Million Years Off" (an episode which features Once Upon a Time guest star Sage Brocklebank). The home of Fox Mulder in The X-Files episodes "My Struggle" (an episode which features Once Upon a Time guest star Giacomo Baessato),[ The location of a village in Japan in the Legends of Tomorrow episode "Shogun". The crash site of Air Force One in the CW Supergirl episode "Resist" The home of Bass Reeves' in the Timeless episode "The Murder of Jesse James". A crop field in the Wayward Pines episode "Blood Harvest" and the abandoned home of Pamela Pilcher in the Wayward Pines episode "Once Upon a Time in Wayward Pines" (both episodes feature Once Upon a Time guest star Kacey Rohl). The Devil's House in the Riverdale episode "Chapter Eighteen: When a Stranger Calls". The Cartwright house in the Batwoman episodes "Mine Is a Long And a Sad Tale" and "Off With Her Head". The farmhouse also appeared in fellow Arrowverse show, DC's Legends of Tomorrow in season 6, episode 14, titled There Will Be Brood. It was used for Spooner's mother's home.