I make a living buying and selling used books. I browse the racks of thrift stores and library book sales using an electronic bar-code scanner. I push the button, a red laser hops about, and an LCD screen lights up with the resale values. It feels like being God in his own tiny recreational casino; my judgments are sure and simple, and I always win because I have foreknowledge of all bad bets. The software I use tells me the going price, on Amazon Marketplace, of the title I just scanned, along with the all-important sales rank, so I know the book’s prospects immediately. I turn a profit every time.

I’m pretty sure I first heard about the practice of shopping for books with laser scanners in a story on NPR, which, as I recall it, disparaged their use as classless. And, really, it is precisely this. The book merchant of the high-cultural imagination is a literate compleat and serves the literate. He doesn’t need a scanner, because he knows more than the scanner knows. I fill a different niche—I deal in collectible or meaningful books only by accident. I’m not deep, but I am broad. My customer is anyone who needs a book that I happen to find and can make money from.

“I heard about what you’re doing,” says someone from my old MFA program. “It’s a really creative way of educating yourself.”

“I don’t read the books,” I say.

“But you … look through them?”

No—I look through the books only to see if there are marks or stains.

Another friend, pained by the intensity of my nonreflectiveness, tells me, “If you could just specialize in a certain kind of book …” Sure, but if I started to do that, I’d make only a fraction of what I do now using the scanner-judges-all method.

My scanner lies at the end of a cartridge that is fitted into a Dell PDA—a species of technology now obsolete for nearly every purpose but this one. Anyone with a smartphone can scan barcodes on books, but these people aren’t the competition, exactly. Smartphone scanner applications, which interpret photographic images of barcodes and then look up the corresponding products on the Web, work too slowly to be tools for the professional. With the PDA and laser scanner, I work at the speed of the retail cashier.

My PDA shows the range of prices that other Amazon sellers are asking for the book in question. Those listings offer me guidance on what price to set when I post the book myself and how much I’m likely to earn when the sale goes through. The scan happens fast and the prices are stored locally, in a database that I download onto the device from a third-party company. If, according to the settings I’ve plugged in, a book is sufficiently valuable, the program shows me a green “BUY” bar across the top. If it’s a dud, I see a red bar: “REJECT.”

When I first started this work, I would wake up every morning with fingers stiff from prying apart books in order to get a better look, and a clear shot at the barcode. On average, only one book in 30 will have a resale value that makes it a “BUY.” One man’s trash is, of course, nearly always another man’s trash.When I find a good one, I get a little feeling of violent achievement, and I hide the book away immediately. (Sometimes resellers will carry blankets around to throw over their piles of treasures.)

The old-fashionedness of my PDA echoes the marginality of the work I do. I rely on a technological castoff to search through other people’s castoff merchandise. Thrift stores and even library book sales often present books jumbled in boxes on the floor. I root through these. If there’s another guy scanning near me—a competitor—I go faster. (And it’s almost always a guy, notwithstanding the pair of redheaded, cheerleader-type twins I see at book sales around Chicago.)

At first, the books that I had for sale fit nicely on a single bookcase. Then two bookcases, and then two more—tall ones. Then also the shelves at the back of a closet, and then a second closet. I now have about 1,000 books listed on Amazon. When it feels as if someone’s always buying something, that means the business is going well. Lately, I’ve been averaging about 30 books sold per day. I pull them down, fit them into padded envelopes, print postage at home, and drive my packages to the post office before closing time—six days a week. After this, I usually go out looking for more stock, and after that I often stay up late making new listings online—describing the physical faults of my books, deciding on prices. I work up to 80 hours a week.

If I can tell from a book’s Amazon sales rank that I’ll be able to sell it in one day, I might accept a projected profit of as little as a dollar. The more difficult a book will be to sell, the more money the sale needs to promise. You learn to let your eyes be drawn, when you go through a shelf or pile, to those superficial aspects of a book’s exterior that communicate value. Is it shiny—newish? Do the fonts feel contemporary? Is it well-designed, and therefore marketed to people with taste, and therefore expensive? You can almost always judge a book by its cover. Size also correlates with value, roughly, and so bigger books are more exciting finds. A textbook in its current edition might sell for $100 even in awful shape. You leave alone those recently popular titles whose value has evaporated—any book about George W. Bush, the various boom-time printings of Barack Obama’s two books—and you learn what sort of unknown books are low-percentage shots: pulp paperbacks, kids’ books, anything about the dietary benefits of soy.

It’s also rarely worthwhile to investigate anything that looks truly old or anything that doesn’t have a barcode (which usually means it’s old). It’s certain that I’ve passed by very valuable old books. I do carry a smartphone along with the PDA so I can search online for curious pieces from the pre-ISBN era. But that research hardly ever pays off. My work is crowded by artifacts of thought and expression which the culture hasn’t wanted to conserve. And, of course, the number of actual objects the culture conserves is even smaller. If enough people want to read an older work, it comes out in a new edition. More often, I find the old editions, variably handsome or yellowed and trashy, which will almost all be tumbling in the darkness of a dumpster soon after I pass on them.

There is constant competition for the small minority of books that will not end up in the trash. Adults in cushiony white sneakers actually run into book-sale spaces at opening time, empty plastic bins raised over their heads. We all go as hard as we can until all the good books are gone. Resellers are almost always quite polite to one another in these situations; we understand each other. Also—as people who work mostly alone and have gravitated toward the bottom rungs of professional prestige—we are not at ease with being outwardly competitive.

On the thrift store end of things, the competition is more phantasmic. At most locations, you see fellow scavengers infrequently, but you can tell when they’ve been there. I can often “read” the relative disturbance suffered by a body of books from a distance, and based on signs that I’d be hard-pressed to objectify—the intuition of the tracker! Whoever gets to a trove of books first is going to try to take everything that’s good, so virginity is paramount. To increase your odds, it’s important to maintain a territory. There are certain stores I go to almost every day. This behavior starts a positive feedback loop: If other buyers find little to their liking, they’ll show up less frequently, and I’ll get even more.

There is competition in the used book game because it is actually possible to make a living doing what I do. I see my adversaries packing their hauls into decent cars, sometimes with the help of family members. A good load of books found all of a sudden might be resalable for many hundreds of dollars. With diligence, someone working alone can make $1,000 per week; with a more insane commitment, or with the help of a wife or child, the business might yield more, especially once a sizable inventory has been built up.

If it’s possible to make a decent living selling books online, then why does it feel so shameful to do this work? I’m not the only one who feels this way; I see it in the mien of my fellow scanners as they whip out their PDAs next to the politely browsing normal customers. The sense that this is a dishonorable profession is confirmed by library book sales that tag their advertisements with “No electronic devices allowed,” though making this rule probably isn’t in the libraries’ financial interest. People scanning books sometimes get kicked out of thrift stores and retail shops as well, though this hasn’t happened to me yet.

I’ve had just one confrontation while doing my job, with an elderly man in a suburb. We were in the library’s book-sale room when I overheard him telling his friend that the two of them were surrounded by a——-—that is, the people scanning. “It’s a business,” I said, but I felt all locked up and couldn’t bear to turn and say it to his face. “This is a library!” he spat. “You don’t work here—you don’t work at the library!” He told me that he had 10,000 books in his house, and that he’d read them all. A dozen other people kept scanning silently. Later on, in the parking lot, I got some empathy from my comrades, but they quickly started to speak about their work with the same hunching defensiveness I had put on with my challenger.

The bibliophile bookseller, and the various other species of pickers and flippers of secondhand merchandise, would never be reproached like this and could never be made to feel bad in this way. Record geeks are, obviously, crazy music fans. The dealer in used designer clothes or antique housewares, when he considers a piece, can evaluate its craftsmanship and beauty with the same gaze he uses to appraise it. But the aesthetic value of a book—its literary merit—doesn’t have anything to do with its physical condition. Besides, libraries are for readers, not people who see profit in the shelves. When I work with my scanner and there’s someone else shopping near me who wants to read books, I feel that my energy is all wrong—high-pitched, focused narrowly in the present, and jealous. Someone browsing through books does it with a diffuse, forgetful curiosity, a kind of open reckoning that she learned from reading. Good health to you, reader. One day I will be like you again.

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