It's usually a compliment when someone successful sees past versions of themselves in you.
Not so for Mark Cuban.
On Friday's episode of ABC's "Shark Tank," Cuban offered a big deal to Collars & Co., a Bethesda, Maryland-based menswear brand that makes casual polos with dress collars. But he did it cautiously, because founder Justin Baer's pitch showcased an off-putting trait that Cuban recognized from his own past.
"He reminded me of me, I'm not going to lie," Cuban said. "When you're young, you don't know what you don't know. I did a lot more talking than listening."
Cuban and guest Shark Peter Jones teamed up to offer Baer a $300,000 investment, plus a $700,000 line of credit, for 10% of Collars & Co. The deal reflected the company's high sales — $5.4 million since its inception in 2021, at the time of taping — but came only after rounds of tense negotiations.
It started when Kevin O'Leary offered $300,000 for 10% of the company, saying it was the first time he'd ever extended an offer to a shirt company.
Bringing in $5 million in sales so quickly meant Baer "must have executional skills ... that others [in the industry] don't have," O'Leary said.
Baer scoffed at the offer, saying he'd give up only 4% of his company for $300,000.
O'Leary's valuation underestimated Collars & Co. projected growth, Baer added: The startup was on track to bring in $10 million in revenue in 2022, at the time of taping.
He said he also didn't want to give up 10% of his company. Instead, he wanted mentorship and a line of credit to build inventory, invest in marketing and grow his team.
The other Sharks expressed surprise. Daymond John said rejecting O'Leary's deal was foolish, because Baer's shirts would quickly go out of style if the economy entered a recession.
Jones then made the same offer as O'Leary, saying he'd make a better business partner. He'd previously invested in fashion companies, which had existing infrastructure that could help grow the Collars & Co., he said.
Baer again rejected the offer. The tank erupted.
Cuban asked Baer how much money he'd actually need to reach his goals. The response: a $700,000 line of credit. Cuban said he'd partner with Jones to add that line of credit to the deal on the table — but Baer said he'd only accept giving up 5% of his company.
Jones tried to explain why he thought 10% was a fair offer, especially between two Sharks, but Baer kept interrupting him. As frustrations mounted, Cuban noted that the offer benefited Baer more than the Sharks.
"If [Jones and I] don't do this deal, our lives aren't going to change. We're still going to be f---ing rich," Cuban said.
The other investors withdrew from consideration, leaving only Cuban and Jones' offer on the table. Baer asked if they'd take 7% of his company. Cuban said 10% was their final offer.
With no other options, Baer accepted.
Once Baer left, Jones and Cuban wondered how the trio would work together over time — but Baer seemed satisfied with the negotiations and deal.
"It means a ton that Mark Cuban and Peter Jones are mentors now," he said. "Hopefully one day I'll be sitting next to them in one of the Shark chairs."
Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."
Want to earn more and work less? Register for the free CNBC Make It: Your Money virtual event on Dec. 13 at 12 p.m. ET to learn from money masters like Kevin O'Leary how you can increase your earning power.