The parking lot between the arena and the warmup jumps will be available for shade tents and one vehicle at no charge.
There are beeeaaauuuutiful, large box stalls indoors that will be available for rent for the weekend.  This area will be locked when the event is not running.
And a middle option:  there are outdoor box stalls, covered with a fabric roof that will be available for a modest fee.  No ability to lock up unfortunately.  These stalls are located around the side of the arena and at this time we are not sure if there's a convenient door to enter the arena on that side (we suspect you'd have walk around to the lobby or the rollup doors on the shade tent side).