I go there with a friend with a membership card, don't have one of my own
Not everything at Costco is in huge sizes anymore. Here's what I get there for dining at Chez HAL:
Fresh chicken breast sold 2 per pack, 6 packs total. They freeze great and cooking 2 breasts at a time is about 1/2 a regular recipe. The individually frozen ones aren't as good quality.
Case of 8 oz chopped tomatoes in juice, it's going fast!
Fresh lunchmeats, I repackage 4 slices to a small zippy bag and freeze.
Smoked salmon. Truly I can eat an entire package before it goes off, but I also repackage about 6 slices per small zippy bag, amazing how well smoked salmon is even after thawing.
Bags of peppers. I know they aren't organic but they are good quality and 6 peppers per bag for $5 is awesome. They keep for quite a while but now that I've tried Ina's method to roast them I've been doing that and freezing what I don't use right away.
Small zippy bags are a must! I use the gallon ones too and also to hold my knitting. And tp, one can *never* have too much of that on hand.
Their fresh filet mignon and ribeyes are great, but their fresh fish is usually farmed so I don't buy them. To keep the steaks nice I rub them with a little olive oil, then in foil, then in a zippy bag. Never had freezerburn yet. If you do buy fish, cut it into filets or steaks and put in small zippy bags, then fill the bags with water and then freeze. One of my ex's taught me this trick, he fished a LOT and it was a great trick.
Their cheese prices are excellent and are in a good quantity. They had mimolette wedges for $7, at Molly Stones a 1/4 of the Costco wedge was $9!
Their vodka (Kirkland brand) is in a huge bottle but it is made by Grey Goose!!
I hope this helps you. In, be sure to visit the jewelry counter, one of my ex's always bought me baubles there ( he didn't know I knew where they came from), my local jeweler said the quality was top notch - a diamond I have was valued at 2x what he paid for, of course I haven't kept up with prices lately.... I also bought an external hard drive there 750 gigs for $99, I bought one for work last year through Best Buy for $250 and that was a sale price.
It's best to go regularly and see what they get in and try something new now and again.