When I arrived at Jiffy Lube, I noticed they had a new sign up saying that they'd meet their competitors' prices. I got out my cell phone and typed in the lowest prices in my area for an oil change. I knew the Honda dealer and the shop I usually take my car to charge more.
The lowest price came up $19.99 at Firestone. When it came time to pay, the Jiffy Lube attendant said the lowest price he could give me was $20.20. I said that was fine.
Smartphones are a great help for consumers. In the past, comparing prices has been much more difficult. You'd need to make a lot of phone calls. Sometimes, companies wouldn't give you the prices. Often, it took a long time to find someone in the store who could go and look at the item to find the price.
So, be sure to use your smartphone to see if another company has a lower price. Many stores will match their competitor's prices, saving you money.