We have always used one of our travel rewards Amex cards. It did not have to be the Costco one. And you could always use a debit card. Had to do that once when I did not have the AMEX card with me.
I think I’m going to have to wait and see fully and firmly what the Costco Visa deal is. It would seem that would make it very desirable to have their card. However I do have two other Visa’s and don’t really want 3 so I will dump one of them -I’m not fully attached.
That’s the problem with Visas… Ubiquitous. Amex added diversity to the plastic contents of my wallet. 
Right. Wallet diversity. Very important.
Re: the question about returning sheets several years later, my guess is that Costco would take them back. However, for stores with generous return policies, I always consider whether I’ve received fair use out of the product. Those generous return policies incur costs for other shoppers, and I want to be fair.
I had a set of sheets from TJ Maxx tear a couple of months into use. Those I would have returned, had I had the option. But, after several years, I figure it’s time to retire the sheets to the rag bin. Coincidentally, just last week I realized that one of our fitted Kirkland Egyptian Cotton Sateen sheets’s elastic had failed, no longer holding the sheet in place. We must have washed that set a few hundred times, as it is three or four years old. I will be happy to buy a new set the next time I’m at Costco. I wouldn’t dream of trying to take them back.
YMMV
Went onto Costco.com and voila! Green Mountain Dark Magic K-cups. And they are on their way to my house. Best price I have found per cup so far.
Someone asked upthread about blinds/shades from Costco. I can only share about my experience with shutters, but I got an estimate through Costco. Local dealer came out and measured and gave me an estimate which she said was 35% off dealer price vs her usual 30% off she offered. In addition, it would include a 5% rebate in the form of a Costco gift card. I believe the brand was Graeber and they were composite, not all wood. After that estimate, I found someone who made custom all wood shutters for less than half quoted by the Costco affiliate. $12k vs $5k. I am sure it varies by region, but get several estimates/quotes. Costco is not always the least expensive.
They are having a sale on Peets too, starting on Thursday (on line). Even with the sale on Starbucks Thursday, they are still too expensive, IMO.
VaBluebird-
I must have pulled up the wrong k cups. They seem pricey.
VaBluebird-
I must have pulled up the wrong k cups. They seem pricey>>>>>>>
51 cents per cup vs. 55 cents per cup is the next cheapest I have found, both in person and online.
That said, I have gotten other brands on sale dropping the price to maybe 42 cents per cup but they just aren’t good. I want my Dark Magic! At the cheapest price possible!
I have had that coffee.Its good!
Costco just started stocking Salem Baking Company Meyer Lemon Moravian Cookies. They were on sale for $4 something. Delicious and divided into little individual packs of about 21 very thin little cookies. So, a big box will stay fresh for a long time (of course, though, they may get eaten quickly since they are so good!).
Organic eggs 2 dozen are a bargain for 5.99
My Costco now also has organic pasture raised eggs and they are sold in the traditional recycled paper cartons, one dozen at a time. I’ll check the prices next time I go.
I love Salem Baking Co.'s Moravian ginger cookies so I would love to see them (and sugar) in Costco too. I would imagine their savory stuff like cheese straws are good too. I looked on their website and saw some interesting recipes, simple but elegant. I love that the cookies are so thin. The cookie sandwich with butter cream sounds very good. Also, the idea of just putting crème fraiche and a raspberry on top of a cookie sounds good. I’m not that crazy about goat cheese but a small goat cheese ball rolled in crushed meyer lemon cookies and thyme doesn’t sound too bad. https://www.salembaking.com/recipes/
Went there Sunday (closest one is 2 hours away) for an outing. We stock up on their fish. Got a really nice dog bed for $25 and a soundbar we never did do on the big TV.
I tried a sample of the lemon cookies. Really good, and lots of lemon flavor. They’d also make a good crust, graham cracker style, for mini tartlets and the like. I didn’t buy a bag because they were a little too good to keep around the house outside of a special occasion. 
Other things I buy:
Orowheat bread, two loaves @ 1.5 lbs each - $5.69 for a two pack
Eggs - $1.69 for 18 ct
Milk - two gallons for $5 and change
Kerrygold butter (grassfed, for those who like that) - can’t remember the price, but cheaper than the grocery store
Generic coffee / decaf - $9 / $10 for 3 lbs
Ground beef - unless one of circulars has a really good sale, Costco ground beef is the least expensive.
Frozen fruit / veggies
Frozen shrimp - great quality and still cheaper than the supers
Glad you liked the lemon cookies, @DiotimaDM . I love Kerrygold butter but our local Costco doesn’t always have it. I bought some Plugra on sale at our local store yesterday. I like their butter too but I wait for it to be on sale.
We buy the 4 packs of ribeye steaks every few months at Costco. We grill one when we get them and freeze the other three to have later. Also buy their salmon with basil butter and their spinach salad occasionally too. They usually have good deals on romaine and mixed greens too.
The have nice huge kites @ $12.99 right now. Bought one for nephew. They also gave fruit chips that look good–bought a bag for us and one for nephew. Another shopper was by display and very pleased it was in stock. She says they’re delicious, tho not in stock as often as she’d like.
The Kirkland vegetable spray and plastic wrap are excellent staples.
The Kirkland whole roasted cooked turkey breast is an excellent bargain at $3.99 a pound. You can freeze half as its a bit big. But it’s way cheaper than deli meat and it is delicious.