Thrifting is a science, my friends.

Resale is always nice, but with these five hacks for the racks you can double down and earn more discounts on already low thrift and consignment prices.

1. Shop online 

Instead of hoofing it to the store, thrift through your computer. Goodwill runs online auction site ShopGoodwill.com, which draws from locations across the country. Shoppers bid on items during a given time frame. And just like the brick and mortar stores, there are treasures, oddities and deals: This week, ShopGoodwill.com had a "Sesame Street"Big Bird full costume for auction with a high bid of $71 eight hours before close, and a 14K white gold, 2 carat marquise diamond engagement ring for $452.99, with bidding ending Friday.

2. Take advantage of tech coupons 

If you have a favorite store (and if you don't you may find it here), search for it on Facebook, like or follow for notifications, and watch as flash sales and deals roll down your screen.

Even if there are no sales, many stores post their newest and best acquisitions. When that must-have Louis Vuitton purse photo pops up, you can be the first on the scene to bag it.

"As soon as we get them, we sell them that day," said Susan Walter, owner of Roswell's Fashion Finders Consignment. "Usually you can get them a third of the price of retail."

Stores sometimes offer text messaged coupons. Though often the same ones posted on their web sites or Facebook, receiving store texts is a great way to be the early bird if you are out and about.

3. Join the party 

Did someone say, "road trip?"

Thrifting Atlanta, founded by fashion blogger Keren Charles, is a business, a social forum and a touring company rolled into one. Customers on the Thrifting Atlanta Facebook page, more than 25,000 members strong, post best finds or tips on how to save at thrifting. One member posted that she never left home without cords for tying larger items to her car.

For face-to-face savings, Thrifting Atlanta also organizes thrift and consignment store bus tours around Atlanta and nearby cities like Athens. Attendees are chauffeured to vintage, consignment and thrift stores where they get discounts specially priced for Thrifting Atlanta members.

"I've had people who have flown in from other states, because they've heard about Atlanta. They love Atlanta thrifting," said Charles. "They think it's where it's at."

Right now, Thrifting Atlanta is offering a season pass for the rest of the year at $29, plus tote bags for $9.99 to $13.99. Customers can take those tote bags to the stores listed on the web site for discounts year-round. Charles said she is launching a nationwide Thrifting Atlanta app for Apple and Android next month.

Fashion Finders also brings camaraderie to the consignment party. The store hosts a Girls Night Out once a month that offers a "Sales, snacks and sips" after-hours event.

"The GNO, it's really a fellowship," said Connie Cheek, East Cobb resident and Fashion Finders customer. "It's not a secret society, but it's like we're in the know."

4. Shop early, shop often

Trenise Lyons, Goodwill marketing manager, said it's best to shop Goodwill's 58 local stores often, since inventory changes daily at each location. She also said Goodwill of North Georgia now uses its Facebook page and Instagram account to notify customers of the weekly deal tag color for an extra 50 percent off items.

Another good timing rule is to shop resale near the end of a season, when stores are trying to make room for more inventory.

5. Finally, sell before you spend 

"I lost an awful lot of weight last year, and I actually sold my clothes there and replenished my wardrobe," Cheek said. "And many of the things there haven't even been worn. I think it's just the best bargain around."

Charles said selling your own used treasures is one of the best ways to save money at thrift and consignment shopping. Many stores, such as Rag-o-Rama and Uptown Cheapskate will take consignment sales of your used clothing, then give you cash or store credit on the spot.

Charles also suggested Tradesy and Poshmark as online places to clothing drop before you shop.

MORE: Here are Atlanta's best thirft and vintage stores

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