Ga. Code § 48-5-450
Any owner who contests the assessment of an ad valorem tax against a motor vehicle may purchase the license plate without payment of the ad valorem tax, and any owner who contests the assessment of an ad valorem tax against a mobile home may secure a decal for the year in question, by filing with the tax collector or tax commissioner an affidavit of illegality to the assessment together with a surety bond issued by a surety company authorized to do business in this state or, in lieu of such bond, a bond approved by the clerk of the superior court of the county or a cash bond. Whatever bond is filed shall be in an amount equal to the tax and any penalties and interest which may be found to be due. The bond shall be made payable to the tax collector or tax commissioner and shall be conditioned upon the payment of taxes and penalties ultimately found to be due. The affidavit of illegality and the bond shall be transferred immediately by the tax collector or tax commissioner to the superior court, shall be filed in the superior court, and shall be tried as affidavits of illegality are tried in tax cases. Any owner who contests the value assessment of a motor vehicle or mobile home may appeal such assessed value as provided for in Code Section 48-5-311, insofar as applicable.
OCGA § 48-5-450