Depends on local events. I've seen anywhere from $10 to $40. Good luck.
Using around $20, I think. It can be more expensive if there are events going on around, like a concert at mecu Pavilion or and O's game. Also, if you go to any of the bars at Power Plant Live, a number of them will validate parking and it will be discounted (can't remember if that was before or after 9pm). Just ask the bartenders!
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