Shopping at thrift stores, flea markets, and estate sales can be overwhelming. With the sheer volume of stuff, how do you know where to start? How do you spot the gems in the middle of all the… well, trash?

As a professional reseller who has been combing thrift stores for the better part of 30 years, I can help. If you're ready to cut your shopping time in half, score better deals, and walk away with bragging-worthy finds you can trade for cash, read on.

From hard-to-find household items to money-making resales, everything in my “Thrift Shop Like a Pro” series qualifies as a BOLO (Be On the Look-Out for) item. When you find it, buy it!

Featured Find: Vintage Concert T-Shirts

Rather than a specific brand of item, this month's installation covers an entire category: Vintage concert t-shirts. Full disclosure: The last concert I attended was during the Clinton administration (Tori Amos, 1996, thank you very much). But staying on top of the reselling game means following buyer demand and buying outside of my comfort zone.

Like most other popular collectibles, the demand for vintage t-shirts is driven by nostalgia. Today's buyers are predominantly middle-aged with a fair amount of disposable income. They grew up in the 1980s and 1990s and want to recapture the magic of that Aerosmith concert in the summer of 1983 or relive an REM show they snuck out of the house to see.

Fortunately for shoppers, most thrift stores barely glance at the contents of a t-shirt before setting a price. The staff simply does not have time to process the laundry so carefully. Especially in smaller markets, gems from the musical past can easily go unnoticed.

Why buy it?

Sure, threadable concert tees might not be your idea of ​​high fashion. But bless those keen shoppers who can't get enough of them. The resale prices for authentic Vintage Concert t-shirts are out of this world. Besides Harris Tweed and Levi's “Big E” denim, few other clothing categories are as constantly in style.

On Etsy, this Electric Light Orchestra t-shirt promoting the band's 1977 The Big Night tour is priced at $1,550. On eBay, this 1978 Neil Young and Crazy Horse concert t-shirt sold for $800 and the highest bid for this 1992 Morrissey t-shirt was $577.89.

And those are just a few highlights. Thousands of vintage concert items are for sale right now on various resale sites, including vintage hoodies, posters, and ticket stubs. Although it can be tedious, make it a habit to check the racks for t-shirts and sweatshirts the next time you go to a thrift store or garage sale; it might be worth it.

what to look for

Most thrift stores are overflowing with t-shirts. And 99% of them are not worth much more than their second hand price. Finding that elusive 1% requires a keen eye that can quickly scan and spot a treasure ripe for resale.

This is what I look for in a vintage concert t-shirt:

• Condition: Shoppers expect vintage t-shirts to be “pre-loved.” But stains or tears on the front or back graphics will reduce the value of a jersey.
• Firms: Most bands start out by playing smaller venues where a few lucky fans can get their jerseys autographed. Rare firms (think Jerry Garcia or INXS's Michael Hutchence) can increase resale prices tenfold or more.
• Dates and cities: T-shirts that include tour dates and city lineups tend to sell better than those that don't.
• Maker: From the 1970s to the mid-1990s, there were dozens of manufacturers of print-ready T-shirts. Some of the more common brands include JERZEES, Screen Stars, Champion, Russell Athletic, Hanes, and Stedman. Shirts with original collar tags tend to sell better than those without.
• Single stitch construction: Until the 1990s, most jerseys were sewn with a single line of thread at the bottom hem, shoulder seam, and sleeve hem. Contemporary shirts are double stitched in these same areas. Single-stitch construction can be an indicator that you've found a genuine vintage t-shirt.

Pro tip: Vintage T-shirts of all kinds are a lucrative market for counterfeiters. Learn how to spot a fake by reading The Ultimate Guide to Vintage T-Shirt Authentication at Defunked.