4 Costco Mistakes I've Made That You Can Avoid

I've been a Costco member for over 15 years. And while I'd like to think I've mastered the art of Costco shopping at this point, I've certainly made some mistakes along the way. Here are a few I'll own up to that you may want to avoid.

1. Buying the wrong membership

Before my husband and I had kids, we stuck to a basic Costco membership instead of springing for an upgraded Executive one. This seemed like a prudent choice since we were a smaller household and didn't spend nearly as much money on groceries as we do now.

But actually, not upgrading earlier on was a mistake. First of all, back then, my husband and I made our fair share of Costco purchases that weren't groceries or household essentials. And those would've been eligible for the 2% cash back on Costco purchases you get with an Executive membership. With a basic membership, there's no cash back on your purchases from Costco itself -- though you may be eligible for cash back from your credit card.

Also, Costco's Executive membership is basically risk-free, because if you decide to downgrade to a basic one and you haven't racked up enough cash back to cover the cost of its higher annual fee, Costco will refund you the difference. Right now, a basic Costco membership costs $60, versus $120 for an Executive membership. But let's say you only earn $50 from your Executive membership over a year. If you choose to downgrade, Costco will give you $10 back to make you whole.

2. Avoiding Kirkland products

When I first started shopping at Costco, I'd intentionally avoid Kirkland products because I assumed they were inferior. I quickly learned that not only is that not the case, but often, Kirkland products are actually made by the same companies many of us are already familiar with.

Now I have no idea how much money being a brand snob cost me back in the day. These days, however, I buy plenty of Kirkland products and find that it results in a nice amount of savings.

3. Purchasing bulk grocery items without consulting my family

I often buy products at Costco that I expect to share with my family. But sometimes, I'll make the mistake of purchasing new food items without having my picky children do a taste test first. And you can probably see where this is going.

I've thrown out a fair amount of food through the years by virtue of assuming that my kids will eat a given item when, in fact, they insist that it's terrible. And if you're wondering why, in those cases, I couldn't just consume all of that food myself, try eating 500 multigrain crackers in a three-week period, and you'll have your answer. (That, I find, is a reasonable shelf life once you've opened the package.)

I've learned to remedy this, however, by dragging my kids to Costco on occasion and having them sample new grocery arrivals at the store. Granted, this method isn't fool-proof, because sometimes they'll love something in sample form only to declare it unacceptable when I put it on the table a week later at home. But in many cases, having my kids give their seal of approval has helped me avoid Costco food waste.

4. Shopping while hungry

Shopping when you're hungry can be a bad idea in general. And at a store like Costco, where there's often a new snack item to be scooped up in bulk, it can be downright dangerous. And it's definitely led me to make my share of impulse purchases.

As such, I try to make a point to visit Costco when I'm not utterly ravenous. And if I'm really hungry, that's what the food court frozen yogurt is for.

I can admit that to this day, I still have a habit of buying food items at Costco on a whim -- especially when it comes to the bakery department (darn you, delicious cakes). But for the most part, I've managed to steer clear these other blunders, and that's helped me save money and avoid aggravation.