Just keep in mind one thing--should they deny you for any reason, in the future, any carry permit application that asks "have you been denied a carry permit in this or another state?" you'll have to answer yes.
It may not result in you being denied another, but it could turn into a hassle.
Answering "no" if you were denied could get you in some legal trouble.
If it's really expensive or difficult to get a gun permit, then the criminals either won't be able to afford the permit or won't want to go through the expense or take the time to get one; This disarms the criminals, duh.
But D.C. isn't a state.
There is no permit for DC. It's called being a "police officer" in the city or "business owner".
I am going to take a wild guess that the OP has not gotten a DC permit yet.