Correct he should have a 48" footer. and if he had gotten a permit, (which is required also) he would have know that. They are sold as DIY stuff for sheds and small decks. I have seen decent decks build with them but you have to have a solid foundation below and low decks, like 1' off the ground max.
Truck, Mower, Trimmer, Blower.....same as everyone else.