No ,membership is required for purchases . Its worth the fee . $60 https://www.costco.com/join-costco-quick.html
No, have to be member. 1 yr fee. You can go with someone but they have to pay.
Not that I'm aware of... That being said, you can have a card holder go with you then reimburse them for the bill, as their card has been approved unless you have cash then it's all good.
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