"Grand Slam Garage Sales is owned and operated by high school students," said Keegan Blumenthal with the business.
For a flat fee, the company will run the sale from start to finish.
"We charge $250, plus 30%," he told us.
But if you'd rather do it yourself, Blumenthal has some advice. First, he says make sure it's worth it to have a sale and include big ticket items that'll boost your bottom line.
"Have a lot of furniture. Furniture does sell well," he advised.
Second, market your sale. Set up signs in the neighborhood and advertise for free on Craig's List. At a Grand Slam Sale, an associate will usually stand at a busy intersection and attract people.
Third, set a mental price on each item. Blumenthal says don't spend hours physically tagging items.
"Keep a price in mind and stay very firm on that," he advised.
He says it'll also give you room to bargain.
What about mistakes to avoid? Blumenthal says the customer isn't attached to your things the way you are. So don't overprice items just because they're dear to your heart.
"You got to keep in mind that they are looking for functionality, not necessarily for sentimental value," Blumenthal said.
If you have lots of clothes to sell, don't bother hanging them up. Blumenthal says customer like to rummage through bins.
And finally when it comes to pricing, Blumenthal says keep everything at a dollar to maximize your profit. For example at a Friendswood garage sale, books and clothes were offered at three for a dollar rather than for 35 cents apiece.
Blumenthal says unfortunately people will attempt to steal your things at garage sales, so keep a watchful eye.