People who don't keep kosher cannot believe how much I spend on groceries or the lengths I am willing to go to find things I can cook with. For those of you living on the upper east side (or NY in general) here are some of my favorite places to shop while not spending a fortune.
Brooklyn: There's nothing like going to Brooklyn and bringing back a freezer full of meat and cheese. I actually have a mini freezer for this purpose. Meats are found at great price's at Moishe's and Pic'N Pay. Heck even buying them at Glatt Mart or Pomegranate is cheaper than buying them in the city. Pic 'N Pay is the ultimate cheese store in terms of both selection and price. OF course this requires going to brooklyn and having a means of transporting your goods home.
Pathmark: Get off th 6 train at the 125th street stop and Pathmark is right there. Despite the fact that the store is a very non Jewish neighborhood they have many kosher product becuase they are a national chain. Many of the breads and bakery items that are pre-packaged are kosher. You will also get a much better price on every day staples like flour, rice, bread, pasta etc. Extra savings can be had by singing up for a pathmark card and looking at the circular. I have found the fruit section lacking in quality.
Walgreens: Yeah, I know what you're thinking. It's a drug store. But if you look at the weekly circular you will find great prices on cereal, ice cream aluminum foil and the like. Other drugstores also have sales but they typically have slimmer circulars.
Kosher.com: This is a five towns based company that ships you almost all kosher products. You have to buy things on sale otherwise they are super expensive. The sale price is only slightly higher than brooklyn prices. This is a good option for those who do not have time to shop themselves. Often there are discount codes for 20% or codes to give 20% of your order to charity. You also get a reward for referring friends (If anyone would like me to refer them just let me know).
Costco: This requires a car. It also requires a Costco card. If someone in your family has both card and car convince to take you shopping once every two months or so. You must careful: sometimes buying in bulk is not cheaper than buying on sale at a store like pathmark. Make sure to look at the price per item. Sometimes it is great sometimes it is not. They also have great individually packaged salmons from Kirkman that are certified kosher. Some Costco's, like the one in the five towns, have excellent bakery products that are kosher. The produce is as fresh as it comes and lsts a long time.
The Fruit Cart: These fruit guys are cheaper than thte regular grocery stores and often their stuff is quite fresh. Get to know the vendors in your area to see which has better produce. Try to buy things as close to the day of use as possible.
Always, always look at the circulars for the stores in your neighborhood and sign up for their discount club or card. It doesn't cost anything and often you save.