This is what makes cashier's checks fairly scam-free if you know that.
(Also remember, this is about cashier's checks, not ordinary personal checks.)
Of course this does require that you make your buyer wait while you phone the bank (and possibly do this during bank business hours), get put on hold, etc. And deal with the social discomfort of so obviously not trusting them. And then the risk of what might happen afterwards once you discover they are trying to scam you -- do they just go away or do they get violent or something?
But if you tell them upfront that you'll be calling to verify the check when you meet, it's much more comfortable. Especially because if they're trying to pull the scam, they'll just give up and not meet in the first place.
(Oh, and obviously never accept extra payment and then separately refund a difference. That's scam avoidance 101. If they even suggest that, stop talking to them.)