So as mentioned, there are a few options, the cheapest being South Coast Plaza(free) with roughly an 8 minute walk. The parking structure will currently cost $12 cash, valet I'm sure more. You can prepay your parking if desired (scfta.clickandpark.com). This info is on their web site:
There is a parking structure right next to the theater. I believe it is $10 cash.
Valet parking or south coast plaza mall
Valet parking and parking structures on sight
Valet parking is also available, until filled. Right in front of the entrance.
Parking structures are located on-site.
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