10 Things You Don't Want to Buy at Costco

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Last weekend, as my husband and I watched an Australian comedy, I was startled to hear one of the characters make a remark about picking something up at Costco. For me, Costco is the warehouse store a few miles away. It's easy to forget that there are more than 860 Costco locations worldwide, including China, Iceland, and Sweden. All those shoppers must surely mean Costco prices beat all competitors, right?

No, not always. If you're looking for savings, here are some of the products you may want to consider buying elsewhere.

Anything that won't keep

Here are five items I no longer buy at Costco because I know they won't be consumed before they go bad or expire.

1. Fresh produce

For years, my eyes were bigger than either of our stomachs. I was comically optimistic about how many apples and oranges we would eat in a week and ended up throwing away food I should have been wise enough not to buy in the first place. Picking up fruit at our local farmer's market is always the best bet for our household.

2. Spices

As I was organizing spices after our latest move, I had to wonder how many years I've had some of them. Sure, I may use paprika, cinnamon, and garlic powder regularly, but I can't recall the last time I pulled out the thyme and gave it a good shake. While there's some debate as to how long ground spices last, it's safe to say that it's not as long as I've had most of mine.

3. Over-the-counter medications

All OTC medications have an expiration date, and frankly, I do not have the bandwidth to track how long I've had a massive bottle of pain relievers or antacids in the medicine cabinet. I've learned to pick up small containers of these at Target or Walmart.

4. Cooking oil

I do believe it's been about 20 years since I deep-fried anything, and a bottle of cooking oil could last in our pantry for darn near ever. According to the U.S. Department of Health and Human Services, an unopened container of olive or vegetable oil should be kept in a dark, dry place for six to 12 months after the date of purchase. Once open, they're only good for three to five months.

5. Milk

I'm in a mixed marriage. I love milk, but my husband does not. There is no way on Earth that we could get through two full gallons before one of them spoils. Because I know how important it is to watch the household budget , I only buy milk when I can purchase a single container.

Anything that can be snagged at a lower price elsewhere

One nice perk about shopping at Costco for years is knowing what I can pick up at a lower price elsewhere. While some people love the entire warehouse store experience, the same is not true for all of us.

For those who want to get in and out of Costco quickly, it's easier to look at the overall price of an item -- like a 12-pack of soda or 24-roll of toilet paper -- without breaking it down by unit. However, it's ultimately the unit price that matters.

When the first full-fledged Costco warehouse opened in Seattle in 1983, no one had personal computers at home, and smartphones seemed like something George Jetson would use to call Jane and the kids.

Since that time, we've learned about price comparison apps -- programs that allow you to type in what you're looking for and immediately learn which retailer around you has the lowest price. Apps make it just a little easier to protect your personal finances.

Some of these apps give you instant coupons that lower the price of everyday items. The following five products are items you'll often pay less for at your local grocery store, Target, or Walmart by using old-school or digital coupons.

1. Diapers
2. Toilet paper
3. Soda
4. Pet supplies
5. Holiday décor

Like most things in life, Costco has some great features, but it's not perfect. The trick is to figure out which items save you money at Costco , which you can't find anywhere else, and which you should pick up elsewhere.

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