Backgound Check Fee. There is a $10.00 (non-refundable) background check fee charged by the Tennessee Bureau of Investigation (TBI) with the purchase of any firearm. This fee is a state fee and is not retained by TFGuns. Should you be denied by the TBI from purchasing a firearm when your backgound check is run, the $10 fee must still be paid. TBI background checks are not required for purchases of true muzzleloaders or antique firearms.