Rental contract for apartment in Georgia. Is there a three day grace period when you can change you mind?

My sister signed a lease agreement for a apartment in Georgia.
She now realizes that she can’t afford it. The real estate agent says that she will not only lose her deposit, but will also be responsible for the rent until someone else rents it.
Is there a three day grace period in which she can chance her mind?
Is there a state agency she can call?

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• rent grace period ga