I worked for Costco for about 9 years. It is one of the best places I ever worked and I have great loyalty to the company. I trust Costco to always have the best products at the best prices. I know that anything carrying the label of Kirkland Signature will be the best they can provide.
Case in point is the Kirkland Signature Albacore White Tuna in Water. No one else even comes close to the quality.
That being said, most people know that they don't have "sales" in the strict sense of the word. They do, however, sometimes mark down an item to move it off the floor. How do you know if an item is marked down? Simple. All marked down items will have a price ending in $.97. They also have coupon books through out the year which I'll get to in a bit.
(stock keeping unit) has changed it will also have an asterisk and return with a new SKU.
One of my other favorite things about Costco is the fact that they only carry about 35 hundred SKU's compared to about 35 thousand in the average grocery store. Who needs that many choices? Seriously, have you checked the pickle section lately?
Much of my shopping planning is geared to their coupon books. Why buy 10 boxes of Kleenex in June when in July I can buy the same thing with $3.80 off? Same with vitamins and many of the other staples I always buy at Costco. My usual savings on coupon items is $25.00 to $35.00.
For several years I have relied on Costco Insider to publish the coupon book before the official release. It saves me the trouble of badgering my friends at the warehouse to slip me a copy early. Sometimes they only get it up days before the release, but most times it's at least a week or more in advance - and I thank them.
Costco also has a three week "Black Friday" coupon book with weekly dated deals. Costco Insider has all three weeks posted already.
There you have it - the "secrets."