I'm for an Israeli-style barrier fence across the border's entire length.
I am for the fence as well.
They can add up all the costs for the fence and it will still be less in the long run than what it will costs when a few Islamofascist cross the border and stage an attack on the U.S.
It will still be less than it cost to arrest/adjudicate/incarcerate illegals for crimes they commit here in the U.S.
It will still be less than the costs of giving illegals benefits (healthcare, welfare, housing, education).
Throw in the other negatives about illegals (uninsured motorist premiums is one) and you can logically conclude that:
WE CANNOT AFFORD THIS OPEN BORDER!!!!!