Arizona Scavenger

 is a free quest in Fallout: New Vegas.

Quick walkthrough
After speaking with Aurelius of Phoenix at Cottonwood Cove HQ, he can offer the player character a cap bounty for NCR troops that are killed. For proof bring in NCR Dog tags.

Optional the money reward can be changed to ammo and supplies. For that, go to Decanus Severus. For the locations of dogtags, head over to locations with a heavy NCR presence.