I’ve purchased my share of bad card flips, including this Tim Duncan card at an absurdly high price:

I remember thinking “He’s good!” and “He’s underappreciated!”

I didn’t see the glaring warning sign that said: “don’t buy this card at a higher price than literally anyone else has ever paid.”

(I also didn’t use CardLadder back then)

Anyway, I share these 10 warning signs that I learned the hard way over the years:

For short-term flips of veteran stars, I’m never going after a card that has to hit a price it’s never hit before.

I want to know that the hobby has been willing to pay the higher price before.

For example, Drake Maye’s PSA 10 Prizms hit $350 during his epic playoff run, and now sit around $150. Sure, he might not recreate a Super Bowl appearance, but even returning to $250 would be a nice flip.

On the other hand, LeBron’s pricing has skyrocketed since going to Philly. If you want to earn a profit, his cards would have to continue to go up significantly. I’m skeptical (to say the least) this will happen during the season.

It’s different if you’re going after young guys. They don’t have previous highs to look for, and you can more confidently project increases as they improve.

A one-off injury is okay (like Tatum), but a series of injuries will turn the hobby off (Zion).

I’m a little wary of guys like Lamar Jackson and Joe Burrow. Two guys who can be all-time greats if healthy… but have already had a number of injuries. I’m not off them yet, but I’ve got an eye on them.

The general rule of thumb is to stay away from:

This isn’t a hard-and-fast rule, but rather something to keep in mind.

If a player MUST do something absolutely amazing to increase in price, I’m out.

For example, I love Luka Doncic, but he’s to the point where he needs to be the MVP favorite, go to the Finals, or take his team to 60 wins. I think there’s like a 10% chance of any of those things happening.

Could he increase in value? Absolutely. I just doubt there will be enough of an increase for a profitable flip without one of those things happening.

Don’t buy cards that have just come out. I was dumb and did this in my early days.

Don’t be dumb me 5 years ago.

I usually wait 3 months or so for price to settle, but that can actually be even longer with a hyped player/release.

Wemby decreased for 9 months after his rookie Prizm release, and it was a solid two years before any increases happened.

Gemrate.com tells you what percent of the time a specific card grades a 10 (or “gem mint”).

If you’re interested in grading cards, start there. That’s nonnegotiable. If it’s below 60%, don’t invest. If you’re new, reduce your risk further by shooting for 70%+.

To me, this was perhaps the biggest factor in my profitability as a grader.

Another rookie mistake:

Don’t buy cards that have a small market. So much of successful flipping is based on speed, and having cards stack up on your desk that don’t sell will ruin you.

Go after:

Look on eBay. Are there multiple sales in the last month or (even better) the past week? If a card is regularly selling, they’re easier to comp out and easier to sell.

When working with flippers, I’ll always ask:

“Why do you think this card will go up in value?”

And the most common answer I get is:

“Because this guy is SO good!”

Bzzzzz… wrong answer. He’s already good now, right? So what’s different over the next 3-6 months?

You need legit reasons, like:

Etc., etc., etc.

Stack a few of those, and you’ve got a good flip candidate.

If your plan is to grade, then this is an obvious one.

But even if you’re not grading and you’re just planning to hold and flip, a pristine card is still easier to sell. Your next buyer may want to grade it, and might be willing to pay an extra 10% because you uploaded crystal-clear pictures that show a card in tremendous condition.

Here’s another common “sucker” framework that gets people to bite all the time.

This is the “out of nowhere” season where a player significantly outperforms his normal baseline.

So, think about Cal Raleigh—a solid player who turned in one of the great seasons of all time last year who’s regressed significantly. There were signs though:

Now, all those people who invested at those highest of highs last year are desperately hoping he can return to his 2025 form… which is pretty hard to do considering it was one of the best power-hitting seasons of all time.

This framework happens most often in baseball and football, as it’s pretty much unthinkable that an older non-All-Star could finish second in MVP in basketball.

Like if Austin Reaves finished second next year, that would be one of the most shocking events in NBA history!

With card flipping, you’re laser-focused on a card’s upside…

But just as important is the downside. Make sure you’re walking away if you see any red flags.

There are literally millions of other cards you can buy!

And if you want to learn more about the right cards to buy, that’s what I cover in the Casual Flipper Bootcamp. Enrollment is closed right now, but you can get on the waitlist and be the first to know when the doors open.