Every costco is different. You normally can take a few guests but with the whole covid-19 you can only take 1 or 2 in with you.
2 per membership
You're not supposed to take any, but my son has taken up to two...
Any, just say the group is with you walking in together
You can take as many as you'd like as long as your paying for the product. They won't allow guests to use your membership at the checkout counter
I don't have a specific number, but I have taken 6 guest before and we were just fine.
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