The politics will work against him. Seems like all contracts are going to populated areas with 30 ft walls with slow construction and high costs.
NM border west of Sunland/Santa Teresa is flat and ranchland. Let Fisher scream through New Mexico and flat eastern part of AZ until the mountains.
Trump is fighting to get crumbs. Dollars may be exhausted well before election with only high cost wall.
Have you been down the border in the bootheel? Does not sound like you have. It is not all flat easy to build. There isn’t even currently a road of any kind on most of it to get equipment and material in there.