Agreed!
He's a crook so feel free to string him alooooong for as long as you can.
Have him send you a check, then call the bank where it's drawn from to see how hard it'll bounce.
My "cashier's check" was from a bank branch that no longer existed, and from a company in yet another state up the East coast, that no longer existed either . . . yet the check looked soooo real!
We didn't send the check back, but I did call or text him back to advise that the check was bad and to please send a good check so I could ship him the car