I'd recommend downloading the GameStop app because they typically keep the prices up to date on there. I believe the last time I saw PS4 controllers on there they were around 40 pre-owned and around 60 new.
About 20 30 dollars
You can either call or go visit to see what they have in inventory. Prices vary and depend on condition. Plus whatever rewards you have available on your card would then come off of that.
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