For those on the West Coast, there is the
https://hearstcastle.org/ tour. Quite a place, but probably more so back in the day when filled with antiquities. The workmanship in some areas seemed a bit sub-par for all the money and time poured into it.
In San Jose there is also the gun heiress house featured in the
https://winchestermysteryhouse.com/winchester-movie/ which was a bit grade c.
https://www.insider.com/tour-photos-winchester-mansion-2019-8
A tour of the creepy 24,000-square-foot Winchester mansion in California - Insider After 38 years of construction, with stairs to nowhere and doors that open onto walls, some say the Winchester mansion was built to trap ghosts.