Morkus from Orkus
In contrast, some conservative think tanks have put forth an estimate that it will cost $6T over 50 years to legalize the illegal immigrants in the country today. Sounds like a lot, but it is less per year than the cost of deporting them (per DHS numbers) and the hit the economy would take per The Cato Institute's estimates.
17 billion x 50 years is 850 billion. Add in that 260 initial billion and you're at 1.11 trillion. How is that more than 6 trillion?
You didn't include the numbers for the cost of the fence, but I doubt it's going to be nearly 5 trillion dollars.