Most stores don't charge you a membership fee to walk in the door. But Costco is clearly different.

At Costco, you'll pay $65 a year for a Gold Star (basic) membership or $130 for an Executive membership that gives you 2% cash back on your purchases. And if you're going to be handing over that money, you'll want to make sure you're getting maximum savings out of your shopping experience.

In many cases, that's a matter of using the right strategies and knowing the ins and outs of how Costco works. Here's some insider Costco information that could save you a bundle.

1. Kirkland products are at least 20% cheaper than name brands

Kirkland is Costco's signature brand. And as you might expect, it's generally cheaper than the brands you see advertised all over the place.

But you may not realize how much cheaper it is to buy the Kirkland version of whatever it is you need. Costco specifically has the goal of pricing Kirkland items 20% cheaper or more than the name-brand counterpart. So a shopping cart loaded with $100 worth of national brands might only cost you $80 if you're able to find Kirkland alternatives.

2. Costco's price tags actually mean something

The prices you see listed at Costco don't just represent the amount you'll pay for each item. In some cases, there's a back story.

A price ending in $0.97 means the item is heavily discounted. So if you see useful products with this pricing label, it's a sign that you may want to stock up.

Similarly, items with an asterisk means they won't be restocked once they sell out. If you rely on items in this category, then once again, it's a sign that buying extra could be a good bet.

3. Costco will take back partially eaten food under the right circumstances

It's not a secret that Costco has a very generous return policy. With few exceptions, you can bring back almost any item at any time and get a full refund. But you may not have known that this return policy extends to partially eaten food, provided you're following the rules.

Costco allows customers to return food items -- even opened ones -- that don't meet their expectations. And that could have a few different definitions. Food that goes bad ahead of its expiration date generally falls into this category. But you can also return food if you simply feel that it doesn't taste as good as it should.

However, if you're going to return food due to spoilage, make sure to bring it back before its expiration date. And if you're going to make a return on the basis of taste, make sure to bring back at least 50% of the item.

Also, try not to ask for refunds on the basis of taste too often. The occasional return of this nature shouldn't raise a red flag. But if you do this repeatedly, you could end up risking having your membership revoked.

There's lots to know about how Costco operates. And the more you learn, the more money you can save. For now, though, you can use these tips to make the most of your Costco shopping.

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We're firm believers in the Golden Rule, which is why editorial opinions are ours alone and have not been previously reviewed, approved, or endorsed by included advertisers. The Ascent does not cover all offers on the market. Editorial content from The Ascent is separate from The Motley Fool editorial content and is created by a different analyst team.Maurie Backman has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Costco Wholesale. The Motley Fool has a disclosure policy.

3 Insider Costco Secrets That Could Save You Big Bucks was originally published by The Motley Fool