The outside including the gardens is open to public. There's a fee to tour the inside of the mansion.
Check Groupon, there may be discounts available.
There is normally a small charge. I'm not sure if there is anything special going on. The charge is only around $10 to $15, unless you fall in one of the specific categories that gets charged less. OU students are free. The prices are all listed on their website.
Yes, call first for prices and times
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