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so both buyer and seller are putting something down. Interesting concept. Risky? Yes.

Somewhat risky, yes. But to think of it, a smart contract like this is the only way to make it work.
Damn, this was really troubling me for days! 😅

That's quite interesting. At least the seller gets the collateral if the buyer does not fulfill the agreement.

Yeah, of course, there's risks involved like in anything crypto-related but it's a pretty foul-proof way to sell not-yet-launched tokens. Smart contracts are awesome!