Image: Shopping cart in supermarket © PhotoAlto, James Hardy, PhotoAlto Agency RF, Getty Images

It costs just a dollar. What a deal! Even Wal-Mart, the Goliath of retailing, has added a $1 bargain shopping area in its stores, and you can't walk into a Target without passing the $1 specials right at the front door. Even families with incomes that allow them to shop at the best stores are choosing to cruise the aisles of the local dollar store.

Dollar stores are a bargain hunter's dream. Or are they? In their lust to grab a deal, many shoppers fail to realize dollar stores aren't always the bargain they seem. In fact, some big-box retailers can actually be a better place to buy, both in quality and in price.

Is it really $1?

A lot of really great deals can be found at dollar stores, but you have to search for them. If you look, you'll discover that not all dollar stores are equal. There are some where every item is truly $1 or less, there is the 99 cents store where everything costs that amount, and there are dollar store retailers where items can be as high as $10 or more. To get the best deals at any dollar store, you should determine the items you are shopping for and plan accordingly. Make a list, scour the ads in the paper, and call to see if the store accepts coupons.

The better deals

Here are a few of the best buys to be found at dollar stores:

Disposable items: Paper plates, napkins, party decorations and greeting cards can be found at significant savings. Dollar stores have an abundance of these items in many themes, for $1 or less. If you're buying items for a child's birthday party, graduation party or any other "get-together" where you need paper products, the dollar store is going to have the best value.

Seasonal items: These are another great deal. If you need holiday cards, decorations or ornaments, particularly for a school or office party, shop at a dollar store. They have a good assortment of traditional holiday items for most major holidays. Don't expect them to hold up over one or two seasons, however, and don't expect to find anything unique. The seasonal items for sale here will be very traditional (think pumpkins, Santa and the Easter Bunny).

Baby: Surprisingly, the dollar store is an inexpensive store to purchase a pregnancy test. At larger retailers, these tests can run $7 to $12. AAt the dollar store they cost $1, and they are the same testing kits as those sold at drugstores.

Kitchenware: One of the best dollar-store bargains where you truly get great value is kitchen items. Rubber spatulas, serving tongs, glassware and most kitchen gadgets can be purchased here for 50% to 90% less than at Wal-Mart or Target. Whether you are buying supplies for a dorm or your first apartment or replacing those that are worn out, the dollar store is the place to get them at a great price and at a decent quality.

Books: Children's books are a great buy at dollar stores. You can buy an assortment of easy readers, coloring books and activity books for 50 cents to $1 each. Sometimes the store will even bundle them so you can get several for $1. These stores occasionally have young adult books and novels, though the selection isn't always great.

Other items: Other bargains are paintbrushes and paint trays, masking tape, duct tape and, surprisingly, garden seeds. Unless it's a special paintbrush, many of us will throw it away after one use. It's far better to throw away a paintbrush that cost $1 than a $5.99 paintbrush from a large retailer.

If you look, you can also find great deals on plastic storage tubs, but you do have to look. Many times these items are cheaper when they are on sale at Wal-Mart, and you must carefully look at the quality of the plastic. Some storage tubs from the dollar store simply don't hold up to even moderate use.

Changing shopping habits

There's no doubt there are bargains to be found at dollar stores. According to Britt Beemer, the chairman and founder of America's Research Group, these stores are growing in sales, taking "20% to 25% of annual sales from other retail categories."

The customer base is changing as well. Originally, dollar stores tended to serve lower-income customers, but with the stagnant economy, upper-income and even affluent customers are now shopping there. In response, dollar stores have been adding more merchandise, such as frozen or refrigerated food; they are staying open later; and they are improving their storefronts, creating more inviting stores.

It's cheaper at the big-box stores

While all of these are great incentives to step inside a dollar store, the bottom line that will bring consumers back is price. Often, better deals can be found at larger retailers, particularly when they have sales and when they accept coupons. That's when prices can be significantly better than at a dollar store.

Cheaper is not always better, and you will actually save money by spending a bit more. Purchasing quality clothing, brand-name food products, batteries, electronics and toys will save you dollars and ensure safety.

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