He needs to buy a wall building company. Buy a construction that specializes in building walls. Pay some architects to start making plans. Show those plans to the american people. Make the engineers and architects available for interviews. That’s the ticket that gets him in the white house.
The problem there is that there’s really no such thing as a ‘wall-building company’. There are general contractors, and companies that do heavy construction, but not one that specifically builds walls.
The better idea would be to hire the designers and architects first, have them design the wall (how high, how thick, placement of observation posts & guard towers, defenses, etc.), then hire the contractors on a standby basis. Then, go to the American people and show them the preliminary plans, telling them, “Here’s the wall I was talking about. I’m ready to start construction the day I take office. It’s not a pipe dream...it’s real. We have the plans drawn up and the people ready to get to work. Elect me and let’s get this DONE!”.