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For most folks in the watch business, Geneva’s Watches & Wonders tradeshow is the biggest industry event of the year.. Not so for Sacha Davidoff, one half of the duo behind the beloved Geneva vintage shop Davidoff Brothers. “The Geneva auctions are much, much, much, much, much, much, much bigger because there's vintage being sold,” Davidoff says. “We probably do 10 to 20, maybe even 30 times more business.”

The Geneva auctions, which take place this weekend, are like the flipside to W&W. While the latter deals with the new and modern, the Geneva auctions put a spotlight on vintage, pre-owned, and sometimes extremely old, rare timepieces. I jumped on the phone with Davidoff, who has been attending the auctions for a decade, to ask him the most obnoxiously specific questions possible.

What are the most interesting watches up for sale this weekend?

Davidoff goes into every auction season with a game plan more expansive than anything Steve Kerr can cook up on a charcuterie board. One thing he does is divide the watches he finds compelling into three categories: professional curiosity, meaning watches he aspires to deal with one day; business, meaning watches he might actually buy to deal; and unprofessional curiosity (my term), which are pieces he wants to see just because they’re rare, incredible, or both. These are highlights from that third category.

By far the oddest oddity to be found in Geneva this weekend is a one-of-two Patek Philippe with a chameleon on it. And not, like, a gem-setting that looks like a chameleon (like Rolex’s Eye of the Tiger), or even a cute enamel painting of a chameleon, which would still be pretty wild considering Patek’s conservative design approach. No, this piece has a full TK chameleon figure acting as the bracelet. Only two of these watches exist and the other one is in the Patek Philippe museum, meaning this is the only one that will ever come up for sale. Davidoff has taken to calling it the “Rango,” after the movie starring Johnny Depp as an animated chameleon.

Other highlights include some blinders, like the Rolex Daytona 6269 and 6270. These watches represent two different peaks on Rolex’s gem-setting mountain. Both were made in the ‘80s, long before collectors were used to seeing these types of blinged-out watches. They are both utterly outrageous, but the 6270 is slightly rarer and more desirable because of the baguette diamonds around the bezel and the dark-blue subdials.

Also in the just-let-me-hold-it-for-a-second category is an Audemars Piguet perpetual calendar chronograph. This is the type of watch AP makes all the time now, most notably its ceramic Royal Oak. This watch was made all the way back in 1943 (!!), and the dial has taken on a limey quality.

I just won the lottery (manifesting). How does one bid on these beauties?

Unsurprisingly, making a million-dollar bid at Christie’s isn’t like making an offer on Grailed. This is serious. When registering for an auction, the house will require your address, identification, credit card, phone number, and all that good stuff. “If you're going to Christie's and say, ‘I would like to bid 500,000,’ they will ask you kindly for a bank letter or statements proving that you have sufficient funds,” Davidoff says.

I’m registered. How do I crush my opponents?

For a dealer like Davidoff, the preparation process is extremely intensive. Once the full preview of the auction is released roughly a month in advance he “sits in a dark room, talks to no one, and just goes lot by lot,” he says.

He creates a list of every watch he’s interested in seeing. This year, out of over 1,000 watches, Davidoff whittled that down to 108 pieces to examine more closely.

What happens to those 108?

On the day we chatted, Davidoff attended the in-person viewing for Christie’s. He was interested in seeing 31 watches. “I want to see these in person. I want to loupe them. I want to touch them,” Davidoff says. “I want to get a feeling. I want to see like, ‘Oh, is it dust? Is it a scratch?’ ‘Oh, I didn't really notice that this text was missing.’ ‘I just noticed that this should say Swiss not Swiss Made. Those are the things you only see in person.” Following his inspection, Davidoff culled the list all the way down to three that he’s prepared to bid on this weekend. He’ll go through the rest of the previews at Phillips, Sotheby’s, and Antiquorum slowly adding to that list.

On average, Davidoff says he will end up actively bidding on somewhere in the neighborhood of 30 to 40 pieces.

To what end?

Buying about five to six watches in total.

What factors are used to get to these select few?

Davidoff compares vetting pieces to the three lifelines on Who Wants to Be a Millionaire?. “Pictures, condition report, and then you can phone a friend,” he says. “You're going to click on and zoom in on the pictures—look at all the pictures. Read or request a condition report [a detailed sheet containing all the information about a watch]. Don't be lazy and don’t trust auction houses.” Davidoff says this last rule is important because auction houses work for the sellers, not the buyers. “And, if you're not sure about something, do not hesitate to ask somebody who knows better than you do.”

What’s the best strategy for bidding?

If you have your heart set on a certain watch, the best way to win it is in person. Davidoff makes sure he’s in the room for all his favorite pre-scouted watches. This way, he can bend the ear of the auctioneer to work the bidding increments, or feel out the vibe in the room and see if he can uncover a deal. Another reason to be in the room: “It's something so special that you will never see it again,” Davidoff says.

The next best thing to being in the room? Being on the phone with someone in the room. The auction houses always have a galley of representatives in the room acting as proxies for people over the phone. It doesn’t have the same human touch as being there yourself, but it has more juice than the alternative.

Davidoff’s least favorite way to bid on a watch is using the online system. There’s no wiggle room on the increments for bidding and sometimes there’s a lag, he says. Another major flaw? “When you're clicking that button, it's too easy” to spend more.

Everyone bids differently. Davidoff is flexible in the room. I’ve talked to others, like collector Eric Peng Cheng, who sets an absentee bid and then leaves it be to avoid the temptation of overbidding on something.

What can I do for extra credit?

If you want to be really safe, make a massive Excel sheet with all the watches, like Davidoff does. The dealer lists out the auction house, lot number, low estimate, his target bid, and notes—he writes out his findings in a notebook in person, and then transcribes them into the spreadsheet—for each watch he’s interested in. “I am a geek,” he admits. But this way, when he’s in the room, he can simply consult his sheet to figure out how best to proceed. And that’s how you get your dream watch at auction.

Originally Appeared on GQ