Stop Wasting Your Money at Costco and Start Doing These Things Instead

For many people, joining Costco is a wise personal finance decision. For the amount of money you spend on a membership (either $60 for a basic one or $120 for the Executive version), you might more than make it up in the form of savings on grocery purchases throughout the year.

But certain habits of yours could cause you to waste money in the course of your Costco shopping. Here are three to try to break and replace with better ones to keep your budget in check.

1. Stop buying rarely used items in bulk -- and start buying them at the regular store

Costco's prices often can't be beat on a per-ounce or per-unit basis. And as such, it makes sense to buy items you use on a regular basis in bulk. Where you risk wasting money is bulk purchases of items you only use sparingly.

You might think it's a good idea to buy a massive bag of pecans ahead of Thanksgiving because on a per-ounce basis, you're paying less at Costco than at your regular supermarket. But if your sole need for pecans is to make a single pie, and you don't eat pecans normally, then why would you buy four pounds of them at once?

Pecans, like other nuts, can go stale after a few months. So in a case like that, don't chase the bulk savings. You're not going to save anything if you throw out half of your haul.

2. Stop loading up on produce and check your local discount grocer first

Produce is something that tends to have a very limited shelf life. You might buy a case of strawberries that looks great on Monday, only for those berries to look limp and possibly moldy by Thursday.

That's why it often pays to turn to discount grocers to save money on produce rather than buy it at Costco. It's one thing if you're making a load of strawberry jam and need lots of fresh berries you'll use up in a single day. But buying a week's worth of fruit (or vegetables) just doesn't make sense from a freshness standpoint.

The only reason to buy bulk produce at Costco is if you have a large family and it's conceivable that you will eat up all of those strawberries, or your produce of choice, within about 72 hours.

3. Stop overpaying and ask for price adjustments when you've missed out on a deal

It's happened to the best of us: You buy your favorite crackers or granola bars or chips at the grocery store only to see that same item go on sale a week later -- after you've already opened your box.

The good news is that if you shopped at Costco, you're not stuck paying the higher price. Costco will give you a price adjustment for items purchased within 30 days of a sale. But you need to take the time to go to customer service and ask for one. Since it's an easy way to get some money back, why not do it? You can also request a price adjustment for online purchases by logging into your Costco.com account.

While Costco offers plenty of savings opportunities, certain mistakes might cause you to waste money. Try to avoid these three, so you can make the most of your membership without spending more than you have to.