Buy a car in Canada and drive down or buy it in the US

[claus]

Hi,

Does anyone know if it's cheaper to buy a car in Canada and drive down to the U.S / import it or is it better to wait until I get into the U.S and then buy a car./

Do I need a California driver's license to buy a car in the U.S. How would the process of buying a car in the U.S with a Canadian driver's license work.

Car I'm looking at : BMW I4 https://9apps.ooo/

Thanks guys