Yes, you can rent this castle for events. How about a Halloween Party?
Boldt Castle is a beautiful century-old castle built by George C. Boldt, Waldorf Astoria Hotel proprietor, as a token of love to his wife Louise. With the sudden death of his wife in 1904 George C. Boldt has stopped the construction being struck with grief. After seven decades of abandonment the castle was acquired by Thousand Islands Bridge Authority in 1977 and has been rehabilitated ever since
I really couldn't put all of the information on his spectacular castle
here is the link http://www.boldtcastle.com/visitorinfo/