There is a shuttle every 10-15 min
Return is very quick if you're leaving rental on credit card. Not sure about shuttle.
15-20 min. No more.
15-20 min. Just make sure what terminal you have 2 or 3. If it helps pull up to delta do curbside check in and drop luggage then return car. Much easier.
About 15 minutes
If there arenalot of people waiting you may have to wait for another as they are very small and only fit so many people.
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