The gift shop and grounds are accessible but the mansion isn't
No, it isn't
He can buy the VR video and watch it with VR headset with smartphone, headset cost less than $20 on Amazon.
Really, no. Windy, narrow passageways & stairs. Sorry about that
He'll have access to all the grounds and gardens but unfortunately as for the tour inside the house it'll be provided through video.
There is a video tour though. Ive never seen it but I did hear them talking about it last time I was there. You should be able to contact them by phone to get more info
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