The large, vacant 150-year-old building that was once home to Col. Granville and Henrietta Haller, renters and raccoons, seems destined to become a haunted house.

“It’s so spooky already, it seems like a waste not to take advantage of it,” said Lynn Hyde of Historic Whidbey, the nonprofit group that owns the house.

This October might be the be one of the last chances to experience the Haller House and its peak spookiness, with a series of planned renovations on the horizon.

From 5-7 p.m., tonight, Oct. 26 and from 4-6 p.m. tomorrow, the historic structure will be open as a kid-friendly haunted house, admission by donation. The entrance will be on the Main Street side of the house.

And on “Haller-ween,” the living will have an opportunity to potentially commune with the less-than-living residents of one of Washington state’s oldest homes. A local spiritualist and Whidbey Paranormal Investigators will help locate any lost souls who might be present and maybe find out some things that aren’t in the historical record.

As to whom might make their presences known, it could be the Hallers — who lived in the house for a little over a decade — or another family that called it home for 50 years, Hyde said. The building might have also been used as a boarding home and rental at one point, so any number of spirits could be hanging around their old haunt.

Entrance to the paranormal investigation is $20 and goes from 6:30 to 9 p.m., Oct. 31.

The proceeds from both events go toward the building’s rehabilitation work, which includes a long and expensive list. The idea is turn the largely unchanged historic building into an interpretive space, where people can learn about the house and the state’s territorial period. There are also plans to turn part of it into a 19th century-style mercantile and soda foundation store.

The house, built in 1859, still lacks central heating, electricity and barely has plumbing.

Although it might still lack modern amenities, it has gained a number of magical and mysterious features this month. A vampire’s coffin, witch’s potions and brews, and even a ceiling that resembles Hogwarts’ great hall are newer features in the house, in part thanks to “some real Halloween fanatics” from the Historic Waterfront Association, Hyde said.

“It’s completely over the top, in the best way,” Hyde said, standing in the “witch’s kitchen.”

When a table in the room was bumped, a series of lights flickered and a maniacal cackle echoed through hallway.

Although the decorations are elaborate and certainly in the Halloween spirit, Hyde said the tours will be kept relatively mellow so the younger participants won’t be overwhelmed.

The volunteers were given a great deal of liberty when it came to setting and transforming the space, given that most of the interior will be renovated soon. Little concern was given for the nails in the walls, staples or “blood” splatter, said Hyde.

However, the events are something the group hopes to host again. She said if the foundation is installed and the building is habitable by next October, there’s a good chance the Haller House will be haunted once again.