MOUNTAIN VIEW, Calif. (KGO) -- With inflation at its highest level in two decades, no one wants to pay more than necessary. Unfortunately, that's exactly what's happening to too many unsuspecting consumers.
Every time Sherri Bainbridge opens her refrigerator, she's reminded of how expensive everything is these days.
"I am a single breadwinner and earner and every dime counts," Bainbridge said.
She watches prices like a hawk, making sure she pays the lowest possible prices.
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Bainbridge said she noticed on numerous occasions at the Walmart in Mountain View that she paid more than she should have, based on the price listed on the store shelf.
"At first I didn't notice until I would get home," said Bainbridge. That would mean having to return to the store to get a refund for the overcharge.
So she began taking photos of the price listed on the shelves and comparing it to the receipt she received at checkout.
Walmart priced the burritos on the shelf at $2.98, but they came in at $3.42 at the register. That's a 15% increase.
A bag of bagels sold for $3.18 a bag but rang up at $3.88 -- a 22% mark-up.
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Walmart listed its tortillas at $1.41 but scanned at $1.98 -- a 40% difference.
"It's not just a couple of pennies. It's, it was significant -- especially if your, you know, budget's really tight," said Bainbridge.
7 On Your Side brought Bainbridge's concern to Santa Clara County's Weights and Measures Department.
The department immediately went out to do an undisclosed inspection.
"I sampled four items and two items were overcharged," said Chinh Nguyen, an inspector with Santa Clara County Weights and Measures.
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Based on those findings, he went back for a more complete surprise inspection.
He sampled 51 items and found five overcharges of roughly 10%.
"There's definitely a 'buyer beware' type of thing. People need to pay attention to the checkout," said Joe Deviney, also of Weights and Measures.
Bainbridge says the problem is just not limited to Walmart's Mountain View location.
Weights and Measures confirmed that.
ABC7 News obtained results of inspections going back to 2017 through a Public Records Act request.
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Our analysis revealed inspectors scanned 1,848 packages at Walmart and found 124 overcharges, totaling $502. That's a 7% error rate.
Walmart told us it is testing an enhanced electronic shelf labeling initiative and improved handheld app capabilities to cut down on errors.
"With more than 120,000 items available in our stores, we understand our commitment requires continuous attention and innovation," said the company in an emailed statement to 7 On Your Side.
Violations can lead to fines of up to $1,000.
"The fines are not designed to be punitive. It's just designed to wake up the business," Stan Toy of Weights and Measures told us.
More serious violations can be referred to the district attorney's office.
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"A company may have done this numerous times over many years, then we would seek to litigate," said Deputy District Attorney Jennifer Deng.
At least seven California counties, including five in the Bay Area, reached a $5 million settlement with Target this year after accusing the retailer of charging more than the posted price on an item.
Our analysis reveals inspectors scanned 2,217 items at Target and uncovered 196 overcharges, totaling more than $582. That's a 9% error rate.
Target says: "We've taken steps to improve our processes because the majority of these issues in California occurred when promotional signs were not removed immediately after a promotion ended."
Inspectors scanned more than 1,600 packages at Walgreens and found 79 overcharges, totaling $152 -- a 5% error rate.
Walgreens did not respond to our request for comment.
"This is not right. This needs to be fixed," said Bainbridge.
In our analysis, we only found a handful of undercharges. The overwhelming majority were overcharges. Santa Clara County says it finds overcharges as well at the gas pump and from scales at fish markets and delis, but most of the overcharges are from inaccurate price scans.
Take a look at more stories and videos by Michael Finney and 7 On Your Side.
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