Update or replace electric

[Ben C.]

Hello, I am gutting the interior of an investment down to the studs. The home was built in 1949 and the power is 100 AMPs. I am putting on a nice size addition to the property. Would you simply have the demo company rip out all of the electric (take advantage of the cheap labor) and have electrician re wire the house (nice selling feature brand new electric) or simply update? Thoughts on cost difference and what is wiser?