I live alone and love shopping at Costco. Here are 20 things I buy every trip.

I'm still not entirely sure how Costco keeps its milk and egg prices so low compared to other grocery stores.

I regularly purchase a gallon of Kirkland 2% milk ($3.44) and a package of two dozen Kirkland cage-free large eggs ($3.59).

They last surprisingly long in my fridge, and both have multiple uses, from cereal and scrambled eggs for dinner to recipes for homemade meatballs or brownies.

Pro tip: Don't store your milk in the refrigerator door. I've noticed it spoils much quicker there.

I'm pretty committed to sticking to whole grains whenever possible, and I've eaten Stroehmann 100% whole-wheat bread for as long as I can remember.

Imagine my delight when, on my first Costco trip last year, I realized it was nearly half the price ($3.89 for two loaves) of a regular grocery store.

Pro tip (especially for singles): Immediately store one loaf in your fridge and one in your freezer. Use the soft loaf for sandwiches and the frozen loaf for toast.

Is there a more perfect meal than a classic PB&J? I think not.

With my aforementioned whole grain bread, Kirkland organic peanut butter ($9.99 for two 28-oz. jars), and the (seasonal) Kirkland organic strawberry spread ($6.99), the sandwich feels elevated.

Plus, both items are excellent for singles because they last a long time in the pantry and fridge.

A six-pack of avocados costs $6.49 at Costco — a steal compared to your typically grocery store.

Even though I live alone, I use them in a lot of recipes: on toast, in wraps, on omelets, and even straight out of the skin with a pinch of kosher salt and a squeeze of lemon.

I never waste one. My best tip is to allow them to ripen on your countertop, and keep an eye on them. The moment they feel ripe (or even slightly underripe), transfer them to the produce crisper in your fridge.

I've had luck keeping them perfect and ready to eat for up to two weeks.

You won't find a better value for berries. A 2-pound container of blueberries is $6.49 and a 12-ounce package of raspberries is $4.49.

Because I don't have much of a sweet tooth, these babies curb any craving that crops up. I grab handfuls straight out of the refrigerator throughout the day, use them in smoothies, sprinkle them on cereal or yogurt, sneak them into my PB&Js, etc.

I hit the bottom of the containers before they even start to wilt.

I nearly squealed with joy when I spotted my all-time favorite Chobani less-sugar Greek yogurt at Costco for only $12.99 for a 16-pack.

Even better, this crate goes on special quite often.

The yogurt makes a great quick breakfast or afternoon snack, but I also love cracking one open right before bed. Toss a few blueberries in there, and you've got the perfect balanced treat.

My favorite cereal can be polarizing — its high fiber content isn't always kind to sensitive tummies. But I absolutely love it.

Quaker Oatmeal Squares are hearty enough to withstand any amount of time in milk, great as a crunchy snack right out of the box, and can even be a topping for yogurt.

Name-brand cereals can be astronomically pricey at the grocery store, but the giant two-pack at Costco is $6.99 and lasts forever as long as you keep the inner bag sealed tight.

A-Sha noodles are only $9.49 for 12 packages.

They're surprisingly high in protein (10 grams per serving) and cook to perfection in two minutes. The noodles also make the perfect base for nutritious add-ins like frozen broccoli and peas or leftover protein like chicken breast, steak, or shrimp.

If you're watching your sodium, sub out the prepared sauce packet for a little organic butter, low-sodium soy sauce, sesame oil, and garlic powder to taste.

This is the best budget-friendly, nutritious, and quick lunch or dinner you can make.

Without fail, one prepackaged meal item makes it into my Costco cart every trip.

My three go-to picks are the tortellini pasta salad ($4.99/lb), Asian chicken wraps ($4.99/lb), and roasted chicken-and-Swiss rollers ($5.49/lb).

The trick for singles is to stick to one of these per trip and commit to eating it for lunch or dinner several days in a row to avoid food waste.

When you break the costs down per meal, these items are all a terrific value and a major time-saver.

Kirkland chicken breasts are always $2.89 a pound.

They're already sealed into portion-sized packages, they store well in the freezer, and you can prepare them a million different ways.

I typically season my chicken with generous amounts of olive oil, kosher salt, black pepper, garlic powder, and parsley, and throw them on my countertop grill.

Once it's prepared, I'll keep it in the fridge and toss it into salads, wraps, pastas, and ramen, or even eat it cold out of the fridge when I need a protein boost in the afternoon.

I'm a salty snacker, and Costco sells an 18-ounce, resealable bag of Pirate's Booty for $4.99 (on special).

I get nervous when I run low on the stuff, so it's always in my Costco cart.

The salty snack is an undeniable crowd-pleaser — my nephews always request it when they visit.

Kirkland cheese, fruit, and nut packs are a relative steal at $8.99 for a 16-pack.

I throw them in my bag for road trips, enjoy them as an afternoon snack, and even sometimes eat one for breakfast on busy mornings.

Could you buy all the separate ingredients and make your own for less? Possibly. But for busy singles, sometimes convenience and simplicity are worth it.

Premier Protein shakes cost $26.99 for an 18-pack at Costco.

I stick to vanilla because I'm simple like that.

A generous splash of one of these in your morning coffee in place of creamer and sweetener turns your caffeine fix into a protein-packed treat.

The package is large for someone who lives alone, but they are shelf-stable.

These household staples make their way onto every Costco "best-of" list, but it's for good reason.

Kirkland-brand paper products are an amazing value, great quality, and perfect for single people who live alone. They only cost $14.79 for the 12-pack of paper towels and $16.99 for the 30-pack of toilet paper

I hardly ever have to repurchase these since they last so long, and if you break down price-per-roll, it's a steal.

I'd be remiss not to include at least one non-grocery item on my must-have list.

Costco has great prices on all sorts of quality apparel — Kirkland leggings are still my favorite after trying many other brands.

But I included the Puma athletic socks because they're unanimously loved among friends and family. I've even given them as gifts.

The 10-pack is only $13.99.

Note: Prices are based on one Costco location in New Jersey.

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