https://www.ifly.com/piedmont-triad-international-airport/Piedmont-Triad-GSO-Airport-Parking looks like $8 per day
$8 per day for the lot and $10 per day for the garage.
All I know for sure is outside is 10 dollars day.
Depending on whether you park in the garage or out in the open I believe it's between 8 and $10 a day.
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