Selling a car…moving cross country

In the near future, I will be selling my home in California moving cross country to Atlanta. I do not want to ship my car, I’m ready to get another one. Will probably buy a used car. Simply from an ease-of-use standpoint, is it best to use a company like Carvana or Carmax in order a have a car pretty soon after I arrive? The make of the car that I am selling will be different from the one that I am buying so I probably won’t go through a dealer. Thoughts?