Going to Costco? Take a calculator

Which Vita Coco Coconut Juice package is a better buy?

My wife and son like pure, unadulterated, unflavored coconut juice, and I had it delivered every month through Amazon.com's Subscribe and Save program.

Then, Costco Wholesale in Hackensack started stocking it at a lower price.

On Tuesday, there were two packages of Vita Coco juice available -- 6 1-liter containers for $14.99, after an instant $5 coupon, and 12 11.1-ounce containers for $15.79.

I pulled out my iPhone and used the calculator to determine the 6 1-liter containers are cheaper by the ounce, even at the full price of $19.99.

After weeks of eating lettuce from our garden, I bought a 1-pound package of Earthbound Farm Half & Half Organic Baby Spinach and Spring Mix, and was pleasantly surprised to see the price had gone down a bit to $4.79.

Two pounds of sliced Jarlsberg Light Swiss Cheese has held the line at $9.99 after a price increase last year. 

Trader Joe's jumbo and regular hot dogs aren't created equal.

At Trader Joe's in Paramus, a calculator comes in handy, but what you really need is a magnifying glass to go over some of the labels.

Both Trader Joe's Jumbo Franks and Trader Joe's All-Beef Hot Dogs are uncured and free of harmful preservatives.

But only the smaller hot dogs are made with beef that is free of animal antibiotics and growth hormones.

At Trader Joe's, heirloom tomatoes from Pennsylvania and corn from the Carolinas.

Trader Joe's in Paramus seems to have forgotten New Jersey is the Garden State, which grows world-famous blueberries, tomatoes and corn, among other crops.

At the Paramus store, I went looking for Jersey corn, but found ears from the Carolinas. Heirloom tomatoes came from Pennsylvania.

So, I picked up 3 16-ounce packages of Trader Joe's Organic Whole Wheat Spaghetti, Fusilli and Penne at the excellent price of $1.39 each.