Found this tactic today, whilst screwing around. Make sure you’ve finished “Old World Blues” Or you may experience SPOILERS. This guide can get you about 3,500 caps per run and you can get about 3-4 complete runs. Quick thing: I know it’s not the best way to make money, it’s just a suggestion! No need to tell me how your way it better. Thanks!
Step 1 ‘Getting things ready’
For step one, you’ll need to have played “Old World Blues” and finish it, so you can get the ‘Big Mountain Transportalponder!’ make sure you have the sink’s holotape for fiiling empty bottles. Pretty simple, here’s a walkthrough for the entire Quest “All my friends have off switches” [link]
Step 2 ‘Finding the headquarters’
For step two, You’re going to need to find the ‘Sunset Sarsparilla Headquarters’ . I’ll put an image of it on my pip boy for you to see. Pretty simple to find it, and It’s even part of a quest; there’s only a few enemies and I was able to one-shot them with a hunting rifle. (To the head, of course)
Step 3 ‘Getting the bottles’
For step three, all you need to do is collect empty Sunset Sarsparilla bottles. They’re LITERALLY EVERYWHERE. I’ll put up a picture of just one of many walls of crates with 3+ in each. Just ‘e’ then ‘a’ for a few minutes, then you’ll become overencumbered; but no worry, just walk outside and use your ‘Big Mountain Transportalponder!’ and you’ll be right outside the Sink.
Step 4 ‘Filling the bottles’
Now that you’re in the sink, go to the right into the room with the NPC sink. Talk to her about filling bottles, and then fill the bottles. This is probably the easiest part.
Step 5 ‘Selling the bottles’
Now, resist the urge to put your new, beautiful purified water bottles into the refrigerator behind you. All you must do is go to the Central Intelligence Unit And tell him you’d like to buy from him. Scroll until you see the water and sell all of them. From my experience, I got about 3,500 caps from a full run of about 250+ bottles. Not alot of money for Wanderers later in the game; but hey, it’s money.
Step 6 ‘Profit’
Now you have a reasonable amount of money! Blow it all on gambling, gear, or just throw it all on the ground and roll in it. It’s your money, I Don’t give a fu- I mean, care. Enjoy!