The rules are different from state to state. This is just a generic description, you'll have to look up GA laws specifically. It's really not much different than if you told the dealer you would register the car yourself in state. Not sure if they actually do that anymore, but I bought my JK out of state about 2 years ago.
When you go to purchase the vehicle, inform the seller that you are registering the vehicle in another state. They are going to give you a similar temporary registration but you have X amount of days to register the vehicle in your preferred state. Failure to do so could result in void of sale, penalties, repossession, etc. You will have to pay taxes out of pocket, on the spot, for the vehicle at the DMV when you go to register. You will have to have any inspections or emission testing done that is applicable for your state prior to them giving you a registration.
Other than additional paperwork and signatures, this is the only significant difference.