Uh huh. Go look at the price per foot of barrier, then go look at what the eminent domain through several border towns and cities will cost.
The price per foot of the barrier would not have to be nearly that of the federal contracting boondogles barrier. You make the mistake of factoring in massive graft like it is normal. A decent border wall shouldn't cost much more than a highway. I grew up in a mining town and I have seen whole mountains disappear and appear over a summer and it didn't take $ billions to do it if you use earth and concrete.