MILK cows milk is cheaper!!! Sainsburys is £2.25 for 6 pints Costco is about £1.60!!!! I go through 18 pints a week so it adds up.
We buy peppers (6 in a pack) bread (2 pack for £1.80 for seeded granary) part baked rolls/baguettes
Toilet rolls are cheaper, we buy their own brand 3 ply but it does come in a pack of 48!! Kitchen roll is taller and fatter and cheaper Tissues but again huge pack. We use our loft and we have a utility that we stash cans in.
Tinned tomatoes I think are 12 or 16 in a pack but much better quality as is meat/fish/chicken. Obviously it comes in huge packs so you have to have somewhere to store it or freeze it. Chicken breasts comes as a pack of 13!
Washing powder is a 90 or 120 wash, I buy persil which I wouldn't normally.
If you know someone with a card then go round and cost it up. We love it, we are executive members as we spend a lot and then we get 2% back of what we spend.
We have never got sucked into 4foot tall christmas soldier or giant air hockey table but we were gutted to see our Brittax car seat £35 cheaper 3 weeks after we had bought it from somewhere else.
We use Mackro for envelopes/paper, frozen food and home stuff, Costco for fresh food.