I have a friend who has a potentially complicated matter to deal with, and I think we've gotten it sorted, but I figured I'd get some other opinions too, in case we've missed something. My buddy will be moving a fairly large quantity of firearms from PA to TX in the near future...basically the family collection. It's going to be way too many to check as luggage for a flight, not to mention we figured he'd probably get his name instantly placed on the Watch List for trying to fly that many guns!
We discussed shipping them, but paying an FFL $20 per would quickly get exorbitant, not to mention the fact that he'd have to purchase a significant number of shippable cases (hard sided). So what that leaves is driving back, looks like. The guns will be unloaded and inaccessible (back of the vehicle) except his carry piece (when he's past WV or OH and legal to carry again).
Anyone have any input for additional precautions or things to consider? Ownership is not changing hands at this time; his folks are still alive, and will eventually be relocating to the area, and this helps give them one less thing to worry about come moving day. Any potential issues? Should he have a note from mom and dad?

Thanks in advance for any input.