To participate in Nelson's sales, sellers register at her website ( www.lakidsconsignment.com) and use an online program to get their stuff ready. They enter each item on the computer and give it a price. Next, they print out tags and attach them to the items. Then they're assigned a time to drop off the goods, which are inspected for stains, holes or other defects. Sale owners are picky about which items they accept, both to ensure their sales' reputation for quality and to help overcome the stigma often attached to large sales of used items.
"Some people might think it's like a big garage sale," said John Wasson, who runs a sale in Fort Smith, Ark., with his family, and who developed the software used by many event owners, including Nelson. "It's really more like a retail store. It's just that you do it twice a year."
On a recent Tuesday morning in Van Nuys, several days before the sale, volunteers hung miniature dresses, shirts and shorts and covered tables with everything from Elmo dolls and Caterpillar bulldozers to boxes of children's dishes, bottles, books and shoes.
Nearby, an entire room was bursting with stacks of equipment -- including bouncy seats and ExerSaucers (including Rascon's).
Two days later, shoppers swarmed through the doors and hauled items to the check-out area. Each seller gets 65% of the total, and Nelson keeps the rest for expenses and her profit. Sellers can either reclaim items that don't sell, let them go for half price on the last day of the sale or donate them to charity.
Consignors who volunteer to work at the sale can shop the pre-sale (and take home more of their proceeds), which begins a day earlier than the public event.
Nelson also invites pregnant women to arrive early so volunteers can coach them on what they need.
"For a lot of moms, these are convenience things that make your life better, but they couldn't afford them if they didn't come here," said Dawn Ebert-Byrnes, a West Hollywood stay-at-home mom who acts as the sale's floor manager -- one of a 20-person committee that helps Nelson stage each sale.
"The place has become a real community. It's not just about stuff -- although it's absurd to pay retail."
Sale owners across the country say they're always surprised by who typically sells -- and shops -- at their wildly popular bazaars.
"When I started, I assumed my upper-middle-class moms would be my sellers and I would have to market to lower-income moms. I had my fliers translated into Spanish," said Laurie Owens, who runs a sale in Flemington, N.J. "I found that really wasn't the case at all."
Nelson's recent sale also represented the melting pot that is Los Angeles, with stay-at-home mothers in $165 jeans frantically searching crowded racks elbow-to-elbow with screenwriters and nannies. Some came from 30 miles away or farther.
Most shoppers were also sellers. Burbank mom Lisa Manocchia brought seven boxes brimming with about 180 items -- including Thomas the Tank Engine bedding, a Harry Potter game, dishes, clothes and a Spider-Man backpack -- which she expected would fetch about $400.
She planned to turn around and spend just as much, outfitting her 4-year-old son with new-to-him things for summer.
"He accumulates a lot of stuff," said Manocchia, who works in the corporate office of Louise's Trattoria.
"If he hasn't played with it for six or seven months, I bring it here."