 re: Costco ~ factor?
This is an interesting question.
I have had a costco membership for over 3 years now (it's a block and a half away), but I let my membership lapse in March and am contemplating whether to re-up. In the past, I've shared the membership with a friend, but now will probably be sharing with my sister, who's a college student.
I get almost all my HBA and cleaning products at CVS or Walgreens, and find that I get most of it for free or close to free. I was able to stock up on free toilet paper at a grocery store, and probably have enough to finish the year (other than 1 4-pack of double rolls that I got for $1, haven't bought tp since January).
In the past, I always got my milk at costco because they had the lowest prices.. to the extent that the savings on the gallon of milk I bought every week to two weeks put a significant dent in the cost of the membership. Now, though, other stores are more competitive (though, costco may have come down... haven't been in there since March) and I now have a store that doubles, so the $.50/1 milk coupon is now a $1/1, making the price more competitive.
If anyone in your family suffers from allergies, the savings on a 300 ct bottle of allergy meds will save you pretty much the cost of a membership for a year. Generic Claritin will run you around $10, generic zyrtec around $13-15, depending on whether or not you have a coupon.
I found that the 1 lb. clamshells of organic spinach are $3 less than anywhere else in town. In the winter, I go through 1 a month. They have 3 lb. bags of snap peas that are also priced very reasonably and the quality is excellent. Right now, I get the majority of my produce from the farmer's market (I've got a goal to eat more locally grown foods). But now, it's getting too hot for spinach and lettuces, so if I want them, I've got to get them at the store.
I don't really eat red meat, but the cuts at costco look gorgeous, as does their chicken and pork. I've never bought chicken there. Prices are pretty good, but I can do better on sale at the grocery store (just bought around 8 lbs. for $1.47/lb not too long ago). The prices for Thanksgiving turkeys are fantastic... another quick way to make up money towards membership. All their turkeys were 19.99, but they were 20 lb. birds. I was just cooking for me and a few friends, but was able to get a LOT more meat out of my bird, which I froze and used for recipes.
There are some staples for which you don't really see coupons... like, say, balsamic vinegar. I also do a lot of my Christmas shopping at costco, as well as baby gifts, etc.
With the mypoints deal, I think I just talked myself into re-upping! :) | 
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