It is not free. From what I understand when we went, it was only open a couple times a year, and at those times you can purchase tickets to enter. The tours are guided and run those days about 30 minutes apart or so. I don't recall the price but it was around $15-$20 I think.
Not free but worth the price of admission.
When I went to Doheny Mansion I want to see a friend/student perform in a concert. It was free.
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