Whoever picks up the gun (transferee) fills out the 4473. It doesn't matter who pays for it. The FFL holder who performs the transfer could care less who pays for the gun. He cares a lot who fills out the 4473 and is the actual owner of the weapon. The actual owner is the one who fills out the 4473, regardless of who paid for it. Someone else paying for your weapon isn't a straw purchase. We had a lot of people come in to Sportsman's Warehouse who paid for a weapon that wasn't going to belong to them. The owner always filled out the 4473.