Pheeble Will

 is a quest in Fallout: New Vegas.

Bighorner rancher Walter Phebus and his wife, Ethel have traveled to New Vegas on the trail of big-name rancher/robber baron named Heck Gunderson. Walter is bent on revenge after losing land to Gunderson in a shady deal.

Detailed walkthrough
Initiate conversation with Walter Phebus near the Las Vegas Boulevard Station to find that he has trailed Heck Gunderson to the Ultra-Luxe casino. Walter tells you his troubles, and requests that you find out why Heck is visiting the casino. With a Barter check of 70, you will receive 400 caps for accepting this quest. Ethel asks that you to persuade her husband to let the matter go. To accomplish Ethel's purpose requires a perception of 7 and a Speech check of 75 (This will end the quest with an EXP reward of 375).

Speak with Heck Gunderson (accompanied by a bodyguard in the Ultra-Luxe casino) to find out that he is working out a food supply deal with the White Glove Society, and that his son, Ted Gunderson, is missing (NOTE: offering to help find Ted will initiate the quest Beyond the Beef).

Return to Walter with your findings. He will ask you to murder both Gundersons. The reward can be increased by 500 caps for Ted with a Barter check of 80 OR 1,000 caps for Heck with a Barter check of 90, or you may offer to just "take care" of them. There are a few ways to get rid of Heck:

Option 1:

One way to get Heck to a secluded area is to steal something from him and run to the penthouse door. He should follow you. When he gets there, go in the penthouse and run around the corner. Then let him get away from the door so he can't backtrack to escape.

Option 2:

Another (valid, but risky) option is to run into the Ultra-Luxe casino lobby, refuse to hand over your weapons, and kill everyone (though this will obviously lead to substantial drops in karma and White Glove Society reputation).

Option 3:

Completing Beyond the Beef by siding with Mortimer and framing Heck Gunderson with Ted's death will result in completing the conditions of both quests simultaneously.

Option 4:

If you have a high enough Sneak skill, you can slip a silent hold-out weapon in, go to the left side of the bar/lobby, near the wall next to a plant, hide, and kill Heck with a silent sneak attack. No karma loss for this.

Option 5:

Completing Beyond the Beef and siding against Mortimer, but then killing Ted Gunderson might be the best of all options. Then pass the Speech check of 35 with Heck Gunderson to get and 250 caps + 130 EXP, and fame with both White Glove Society & The Strip. Then, pickpocket Heck Gunderson and the casino staff will kill him and his bodyguard for you. Return to Walter Phebus, and you'll get up to 1,000 caps.

Option 6:

Equip a stealth boy and then plant frag grenades in his pocket via reverse pickpocketing.