Keith's Caravan Charade

 is an unmarked quest in Fallout: New Vegas.

Quick walkthrough

 * Speak to Captain Parker regarding Keith's illegal activities.


 * Enter Aerotech Suite 200 and search the desk in the south-west most office for Keith's deck of Marked cards.


 * Speak to Keith regarding the Marked cards (this requires a Barter check of 45 or a Speech check of 60).


 * Return to Captain Parker and tell him what you have discovered. He will reward you with 150 Bottle caps and promise more if you provide backup during Keith's arrest.


 * Should you choose to accompany him, he will confront Keith in Suite 200 and eventually murder him. Speak with Parker after the confrontation for an additional 100 caps.

Detailed walkthrough
Offer Captain Parker a helping hand. He will ask you to find evidence that Keith is involved in drug dealing and crooked gambling, adding the note "Investigate Keith's gambling and drug operations" to your Pip-Boy. Locate Keith's deck of marked cards in a desk in the southwest corner of Aerotech Suite 200.

You can discuss the deck directly with Keith by passing a Barter check of 45, which will allow you to purchase Jet from him, and a Speech check of 60, in which he lets you in on his 'system' for winning at caravan. This does not affect the outcome of the quest.

Return to Captain Parker with your findings. He will reward you with 150 caps, you will be given the option of assisting him in arresting Keith for an extra reward. The Captain will then enter Aerotech Suite 200 and confront Keith, who taunts Parker with slights about his wife. Enraged, Captain Parker murders Keith. Talking to Captain Parker afterward will net you an additional 100 caps.

Bugs

 * If Keith is asleep when Captain Parker enters the building to confront him, Keith will go back to sleep as soon as the conversation is over causing Captain Parker to spin around in circles above the sleeping Keith. You can correct this by talking to Keith.  As soon as Keith gets up off his bed, Parker will kill him.


 * The Barter check for Keith gives 45 experience each time it is passed, even in one conversation. As of PC Version 1.1.1, this bug  can be exploited to infinitely level your character and get the Outstanding Orator achievement/trophy.


 * Passing Keith's Barter check while Captain Parker is on the way to arrest him breaks the quest. You'll be unable to turn in the quest and each time you talk to Parker about Keith, you'll receive the note again.


 * Rex may turn hostile against the junkies, causing Keith to flee and ending the dialogue between Keith and Captain Parker. This may be related to the bug that triggers seemingly random attacks on Rex.  If this bug affects you, reload from an earlier save and take all of the food and water items out of Rex's inventory.


 * Captain Parker may disappear from the game when entering Aerotech Suite 200 to arrest Keith. This can be fixed by reloading a saved game.


 * If the player collects the caps promised by Captain Parker, (This does not work every time) you may speak with him again right after and choose the other dialog to collect a second payment of equal caps.


 * Talking to Keith while Captain Parker is confronting him can also break the quest. Captain Parker will no longer talk to Keith or kill him. This can be fixed by reloading a save. Also using the cattle prod on keith while both he and Parker stare at each other with guns out will kill him and Parker will detest your action saying he didnt want him dead.


 * When Parker is shooting Keith, and if the player talks to Parker before he puts away his rifle, he will keep shooting Keith's corpse. This can be done infinitely many times. Confirmed.