Always did the same thing for my playthroughs. Prep with good sneak skill and the Long Haul Perk, then ensure I get there with a Stealth Boy for good measure. Gets old Elijah every time. Leave the Sierra Madre with 400k caps worth of Gold Bars and Pre-War money, and Fast Travel to the Lucky 38 to drop off the goods.
I usually couldnt be bothered to get the gold The money i got from the casino is usually plenty I love to imagine it sucks even harder for elijah that he got all those techs AND money, yet its all so useless for him.
*Observing how it is possible to escape from the Sierra Madre, with all the gold, without command console or glitch* Step 1. Open and run; Fallout New Vegas. Step 2. New game...
Wait, did they patch this? Back when I first played, Elijah was basically a GMPC capable of seeing through a Stealth Boy and had some god mode awareness of the door with the force field.
One time I didn’t take anything and just trapped him in the vault. Not gonna lie, it was really satisfying. But just about every time, I take that gold.