Shaffer purchases almost everything -- from her blue jeans to her engagement ring -- on eBay.

Although she does what so many other people do, she does eBay shopping better, Budman said.

For example, she got her engagement ring at one-fifth the appraisal price.

She has saved hundreds of dollars by capitalizing on others mistakes.

"Something like 'amethyst' is so frequently misspelled," Shaffer said.

She knows the lesson we all learned in school, it pays to spell correctly. But, in her case, it pays to find bad spelling, Budman said.

"Yes, (finding items misspelled) gives you an advantage, because most people won't ever see that item in their search," she said.

Shaffer does all the right things for a power buyer and seller.

When she sells, she takes her items to Auction Drop, which is just 3.2 miles from her home.

But when she buys, she pounces on the mistakes of others.

Shaffer purposely spells names wrong, like "dimond," because people spell their items wrong so often.

And on one day, she found 60 items with diamond misspelled.

She's saved tens of thousands of dollars on items other people don't often see.

"But remember, the seller loses that much money by misspelling the word," Shaffer said.

So if you put something for sale online, better mind your P's and Q's or else Shaffer just might snap it up, Budman reported.