There’s actually a way to get unlimited caps in Fallout 4, if you don’t want to through the grind and get caps that way, then there is a glitch in the game for you to exploit. The glitch is what’s allowing anyone and everyone to get unlimited caps in Fallout 4. This hole in the massive open word game’s economy appears to have been discovered by the Fallout 4 player community and they have obviously shared it with the rest so that people playing the game can take advantage of it.
The glitch is pretty easy to exploit but keep in mind that it doesn’t work with all vendors. On the vendor panel (right side) first select an entire stage of single ammo type to trade. It’s best to choose the most expensive ammo available but remember to not finalize the trade just yet.
On your panel (left side) select just one piece of ammo of that type to trade it back. Try to sell more of that same ammo, keep one with yourself, sell any amount besides all of it. If you’ve done everything right then you’ve taken advantage of the glitch.
The ammo amount in your panel won’t go down but the trave value at the bottom of the screen will shift in your favor. Rinse and repeat until the vendor no longer has any caps left to give to you.
It obviously won’t be long before Bethesda patches this glitch so if you’re willing to gain the extra advantage in Fallout 4, quickly start collection as many caps as you can, you will no longer be able to use this method once the glitch is patched.