It used to be easier for low-price shoppers to find the best deals. They had their go-to stores where they knew they could find the best prices — one store for shoes, another for electronics.

Then it got even easier. Smartphones equipped with bar code-scanning apps, such as ShopSavvy, gave rise to show-rooming — the practice of looking at a product in a traditional retail store, but then searching for the best price — and usually buying the product — online.

In response, retailers fought back with reverse showrooming or webrooming, actively encouraging shoppers to compare prices online while in their stores and then promising to match a competitor’s price.

Through it all, savvy shoppers were the winners as brick-and-mortar stores and etailers kept one-upping each other in a quest to offer the best deals.

However, the latest salvo in the ongoing price wars requires a different game plan and a different set of tools to determine who has the best price.

When the price is not the price

Most travelers have long understood that as the seats on a particular flight fill up, the price for remaining seats goes up as well. Today, dynamic pricing (also referred to as surge pricing) has found its way into the selling process for a much wider variety of products and services.

Jason Jacobs, founder of a company that makes a popular shoe deodorizer, told CBS News every time his company is written up in the press his product’s price goes up temporarily on Amazon. He attributes the price hikes to increases in demand.

Prices on Amazon change so often that CamelCamelCamel.com, a site that tracks the etailer’s prices, checks the price of popular products three to four times a day. “We wish we could do hourly price checks,” company founder Daniel Green said, “but we’re monitoring 50 million products. This is the best we can do.”

Dynamic pricing is even catching on with traditional retailers. In England, two supermarket chains are replacing fixed price tags on shelves with electronic price tags, which will make it much easier to change prices. The technology is beginning to be used by some U.S. retailers as well, such as Kohl’s and Home Depot.

What’s a shopper to do?

Price match when you buy

Many retailers offer price matching. When you’re ready to buy a product, if you have proof of a lower price being offered elsewhere, the store will honor that price. In some cases, if you find a lower price for a limited time after you’ve made your purchase, the store will give you a credit for the difference. So, before you shop at a particular store, know that store’s price-match policies. Here are some examples.

  • Target
    Target will match the price of a “qualifying” item — either in a Target store or online — if you find the same item for less at Target.com, certain other online competitors, or in Target’s or one of its competitor’s local ads. It will also adjust your payment if you find a lower price within 14 days of purchase. (See Target's price match policy.)
     
  • Walmart
    Walmart has separate policies for in-store and online price matching. For in-store purchases, it matches prices only for identical items found on Walmart.com or Jet.com (owned by Walmart). There’s no mention of price matching after making a purchase at Walmart. For online purchases, the company promises to match prices found at any of several etailers it names on its site. As for after-purchase price matching, the company’s policy says if a product was bought on Walmart.com “recently” and you then find a lower price to “let us know.”
     
  • Best Buy
    Best Buy promises, at the time of purchase or during the return and exchange period, to match prices offered by local competitors (including their online prices) as well as those offered by a handful of major etailers. (See Best Buy's price match policy.)

Of course, each company’s policy includes limitations and exclusions. For example, certain types of products, such as gift cards, usually are off limits, and many stores do not offer price matching from Thanksgiving Day through the week after Thanksgiving. So be sure to read the fine print.

Price match after you buy

As stated above, some stores will honor a competitor’s price after you make your purchase by refunding the difference between what you paid and the lower price you found. However, the time frame tends to be somewhat limited.

Many credit cards offer more liberal policies. For example, some Citi credit cards offer “Price Rewind.” If you find a lower price on a retailer’s website within 60 days of a purchase you made with your Citi card, the company will credit you the difference up to $500 per purchase and $2,500 per year. Other credit cards provide price protection for 90 days. Go to your credit-card company’s website and look for its shopping benefits.

Using Price Rewind, one SMI staffer received $130 back for a laptop computer purchased for one of his sons, and honestly, the website where he found and documented the lower price was pretty obscure! Citi will even search for lower prices for you.

As with store price-matching policies, credit-card policies come with limitations. Citi’s Price Rewind, for example, excludes cars, airline or concert tickets, food, and collectibles.

To do a lower-price search on your own, set a price alert at CamelCamelCamel.com. The service will notify you if Amazon lowers its price for an item you bought (or are considering buying) below a certain amount. Or use a price comparison site, such as PriceGrabber or PriceBlink.

Savvy shoppers can use price matching when making a purchase and then continue to look for even lower prices for 30-60 days after the purchase to see if they are eligible for a rebate from their credit-card company.