John There is no charge for parking. I would buy tickets online. The sales have been going well and the event may sell out.
They always have great signs and people guiding the vehicles for parking. I've never had to pay for parking. Typically I paid for the tix & they let me into the parking area. No other gates to get in. It doesn't look like there is any discount for purchasing tix ahead of time for the Rodeo event.
It's better to buy tickets now. Also they will show you where to park. I would take $5-10 for parking just in case!
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