I only shop for one, but my Costco membership is worth it for 7 reasons — like saving hundreds on gas a year

Thankfully, I don't need tires and batteries on the regular. But when I do, I turn to Costco.

My car requires high-performance tires, which can be hundreds of dollars a pop. They're so costly that I waited as long as possible to replace them last year.

I shopped around for the lowest price and found buying at Costco saved me more than $120 on a set of four. Plus, they came with a five-year road-hazard warranty. Three months later, one of my tires got a screw in it, and I was able to have it repaired at Costco for free in just an hour.

Last month my car needed a new battery. If only I'd remembered Costco sells batteries — I could've saved $100!

Even though I shop for one, I love picking up a few staples at Costco. The freezer section is an especially great spot.

I'm an evangelist for the wild salmon burgers that come frozen in a bag of 12. They're easy to store and to pull out and grill, broil, or pan-fry any night of the week for a quick and high-protein dinner.

The large bags of frozen shrimp are also easy to portion out and use up.

I stock up on big bags of frozen organic fruit for my protein smoothies, too. It's priced well and saves me from having to keep going to the grocery store for those little bags with less than three servings.

I love the large box of Kodiak protein-pancake mix I find at Costco. Smaller boxes of the mix are pricey, so I save by buying it in bulk.

I also stock up on large packs of canned tuna, which doesn't take up a ton of room in my pantry, is so versatile, and lasts for months.

And, when I need a sweet treat, the gluten-free, vegan, and low-sugar Unreal dark-chocolate coconut minis hit the spot with their taste and price. The minis cost way more elsewhere — I can get just over 15 ounces of them for $13 at Costco or a 4-ounce bag at Target for $5.50.

I find it convenient to book an exam with an independent Doctor of Optometry at Costco and then order glasses and contact lenses right there in the warehouse or online.

I've shopped around for my expensive multi-focal contact lenses and typically find the best prices at Costco.

Even better, Costco accepts a whole bunch of insurance plans. And I can buy the Clear Care contact solution I use in bulk for a great price while I'm at the warehouse picking up my prescription, too.

Costco regularly has deals on electronics, but tech purchases come with other perks, too.

I bought a laptop at Costco a few years ago and have made good use of the free concierge tech support that came with my purchase. I would call Costco's tech-support hotline at any hour and I was never made to feel stupid for needing help.

Costco also offers extended manufacturer's warranties on tons of electronics purchased at the warehouse, from televisions to computers to appliances.

Costco sells clothing and accessories from big-name brands and lesser-known ones — all at pretty decent prices.

Last winter, I got a no-name winter puffy coat at Costco for $20 that could pass for a high-end one that costs hundreds.

I've also purchased well-made gloves, shirts, workout leggings, and shorts from Costco. I even bought a couple of sundresses there several years ago and still get compliments every time I wear one.

I live a nomadic life so I drive a lot and always look for the cheapest gas.

Most recently I saved 38 cents a gallon at Costco compared to the other gas stations in the area. That adds up to me saving a few hundred dollars a year on gas by choosing Costco.

Sometimes the lines to get gas at Costco are long, but I can see why. Fortunately, I find they usually move pretty fast.