Papers, Please

Papers, Please is an unmarked quest in Fallout: New Vegas.

Walkthrough
Attempting to mosey onto the New Vegas Strip without enough cash on hand results in the Securitrons warning you to go back the way you came, eventually leading to a skirmish. You can get past security by having 2000 caps on hand, but why do that when you can talk to Ralph at Mick & Ralph's at Freeside? After speaking to him about his special services, he can offer you something, but only after you have impressed The King.

Find a way to do that or continue with some further digging. This reveals Ralph is crafting counterfeit passports. Obviously he want to keep this low key, so he offers you a passport for 500 caps, or with a Barter skill of 50, 375 caps. Once obtained, use it to pass the credit check at The Strip North Gate.