I thought that front hub looked Mack, the rear one doesn't, it looks hendrickson. I think that the hubs, is your best clue as to its homebuilt status. No "manufacturer" is buying mack hubs to mount to a trailer. Built by a construction/ logging/ farmer/ company in the winter to haul some piece of equipment with what was in the boneyard out back. A little of this and a little of that and voila- a trailer is born.
In missouri, a trip to the highway patrol office for a inspection and plates/ title status as a "homebuilt" is allowed. A lot of manufactured trailers with some age on them- and lost titles and registration non-renewals, end up getting reclassified as homebuilt status, rather than trying to sort out old title issues.
I have no idea what georgia rules are.