I'm not sure, If I don't have someone to take me I always just take a Lyft or Uber to the Doraville Marta station and take the train. More of a hassle especially if you have a lot of baggage (I had 4 bags) but Soooo much cheaper and simple in my opinion.
We usually park at Peachy Indoor Parking which is much cheaper than the airport garage. Peachy has a free shuttle bus to the airport & save $30 on a 4 day parking ticket.
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