Investing in Traveling Merchants at Canterbury Common
Go to the area on the very eastern side of the map, in the very middle to discover a town called Canterbury Commons. Once the two costumed NPCs finish fighting, talk to the person named Uncle Roe. Select to talk to him about the caravan merchants, then about organizing them into a special group. Once you can nvest your caps in the merchants, the caravans will have better and more varied merchandise, while the merchants themselves will have better repair skills and more caps on hand at a time. Every initial investment in each merchant will cost 200 caps, while the second will cost 500 caps. With the Master Trader perk, each investment will be cut in half. You are only able to invest twice in each merchant. Once you fully invest in each caravan, the vendor will give you a special gift. Doc Hoff will give you several Stimpaks the next time you talk to him. The amount of Stimpaks varies depending on your level. At the maximum level he gives you seven of them. Lucky Harith will give you one Mini-Nuke, Crow will give you his special Eyebot Helmet, and Crazy Wolfgang will give you a varying amount of Stealth Boys (at the maximum level he gives 6). The merchants and what they carry is below.
Miscellaneous goods and junk, also has best repair skill (at 75) when fully invested.