Urban streetwear boutique Piff hit the social media jackpot a year ago when Vikings star wide receiver Stefon Diggs highlighted the store in a video of his favorite Twin Cities hangouts.

Now Piff has further expanded its street cred, drawing a substantial but undisclosed equity investment from True North Equity Partners to fund future growth.

True North Equity's founder Brian Slipka, a former head of TCF Technology Finance, declined to provide specifics on the convertible debt deal but said it was a minority position "that could lead to a more significant stake down the road."

Piff opened five years ago on SE. Como Avenue in Minneapolis and has become a sought-after reseller of high-priced footwear, hats, sweatshirts and T-shirts.

It trades on nostalgic collectibles and hard-to-find luxe brands such as Supreme, Air Jordan and A Bathing Ape at its brick-and-mortar location and expanding online marketplace.

Ben Alberts, a Woodbury native who played lacrosse at North Dakota State University and the University of St. Thomas, is the driving creator behind the concept. He dropped out of school in 2013 and within a year had opened the store with high school buddy and business partner, Bill Crubaugh.

"I was drawn to the hunt of finding a product that wasn't sold out or was a good value," Alberts said.

The majority of Piff's inventory is "crowdsourced" from people who bring in new or gently used items for trade, cash or store credit. Piff staff verifies the goods' authenticity, and the price fluctuates according to basic market tenets of desirability and scarcity.

Among recent offerings: a heather-gray Supreme Swarovski hooded sweatshirt for $1,775; Adidas Yeezy sneakers by rapper and designer Kanye West for $726; an Off-White brand rain jacket for $725; and a four-pack of Supreme-branded black socks for $58.

About 60% of sales come from sneakers — from vintage Air Jordans to the latest Louis Vuittons, all of which are wrapped in clear plastic and displayed on shelves.

Piff moved in 2018 to its current location, which includes a "speakeasy" backroom with a hidden wall door that can sometimes be used to offer celebrities, such as Diggs, a bit of privacy. (Diggs' video has attracted nearly 5 million views to date.)

Piff is riding the wave of "hype fashion" and urban streetwear, which grew out of the skate and surf culture fashion of 1970s Los Angeles.

The explosive growth of high-end hoodies, graphic T-shirts and colorful footwear has created billion-dollar brands that now have the "cultural clout once reserved solely for high-end luxury labels like Gucci, Saint Laurent and Fendi," according to Vogue Business.

But Piff also is capitalizing on younger consumers' growing interest in buying and selling secondhand items.

"It's giving energy for smaller startups to come in and be part of a huge disruption in the market," Alberts said.

The U.S. resale market has grown 21 times faster than other fashion retail in the past three years, according to market research firm GlobalData. The combined market of resale and thrift-store donations is now worth about $28 billion and could rise to $51 billion by 2023.

The popularity of the luxury market for slightly used goods is reflected in sites such as 1stdibs, which just raised $76 million as it ponders a public offering, and the RealReal, which went public in June with more than 8 million members selling on the site.

Technology is a major driver. Sophisticated algorithms assign resale value at scale, while mobile apps and personalization technology allow shoppers to move fluidly between brick-and-mortar and online-only stores.

Piff has partnered with StockX.com, a leading e-commerce platform for urban and retro streetwear. The relationship has opened up a broader market for Piff's products and significantly boosted sales over the past year, Alberts said.

Alberts and Crubaugh are able to use the StockX platform and data to create their own software technology to streamline the trading process and help customers get the most resale value.

Slipka, the investor, learned about Piff and the world of luxe streetware consignment through his son, who bought and traded gear there. Slipka said he was impressed with Alberts' vision for using technology to scale retail operations and provide licensing opportunities.

True North Equity Partners values Piff at $1 million and believes its investment will spark Alberts' quest to raise an additional $500,000 to enhance and build software applications.

"We're trying to be a tailwind for him to amplify this strategy," Slipka said.