Merchant Empire

 is an unmarked quest in Fallout 3.

Walkthrough
Through discussion with Uncle Roe, in Canterbury Commons, you can ask if the traders could become a unified group. You can proceed with either the Master Trader perk, a high Barter skill, the Black Widow perk, or if you are carrying at least 250 bottlecaps. He offers you a map showing the paths of the merchants and their various trade stops, and the option of investing into any of the caravans. Investing in a caravan allows that merchant to sell a wider variety and higher quality of items. It also raises their Repair skill, allowing them to restore your gear to near perfect condition, as well as the number of caps they have available for trading.

An initial investment of 200 caps can be made in each trader, followed by a second investment of 500 caps (totaling 2800 caps for all upgrades). The Master Trader perk discounts each investment by half to 100 caps for the first and 250 caps for the second.

The first time you speak with a merchant after investing fully in their caravan, you will be presented with a gift of gratitude. The gift differs for all four caravans, one of which includes the rare helmet, Crow's eyebot helmet.

Caravan Merchants
The following merchants correspond to the investments:
 * Armor: Crow
 * Food/medicine: Doc Hoff
 * Misc: Crazy Wolfgang
 * Weapons: Lucky Harith

Reward

 * Improved caps-on-hand total for caravan merchants
 * Improved inventories for caravan merchants.
 * Improved Repair ability for caravan merchants.
 * The next time you meet him, Crazy Wolfgang will give you between 2 to 6 stealth boys (depends on your level).
 * The next time you meet Crow, he will give you Crow's eyebot helmet.
 * The next time you meet Doc Hoff, he will give you between 3 and 7 stimpaks (depends on your level).
 * The next time you meet Lucky Harith, he will give you a mini nuke.

Merchant chart
Amount of caps available depends on the player's level and is random to a certain degree. Caps replenish every 72 hours, but they are also retained, for example: players who routinely use Crazy Wolfgang for repairs will end up seeing higher available caps totals, (in some cases extremely high).
 * {| class="va-table"

! rowspan=2 | Merchant ! rowspan=2 | Ref ID ! rowspan=2 | Goods sold ! colspan=2 align="center" class="unsortable" | Initial ! colspan=2 align="center" class="unsortable" | First investment ! colspan=4 align="center" class="unsortable" | Second investment ! Caps ! Repair ! Caps ! Repair ! Caps ! Repair ! Max condition ! Investment gift
 * - align="left"
 * Crazy Wolfgang
 * 00063c07
 * Junk
 * ≈61-249
 * 15
 * ≈222-648
 * 50
 * ≈483-1197
 * 75
 * 85%
 * 2-6 Stealth Boys †
 * Crow
 * 00063c05
 * Armor
 * ≈61-249
 * 15
 * ≈222-648
 * 40
 * ≈483-1197
 * 65
 * 79%
 * Crow's Eyebot Helmet
 * Doc Hoff
 * 00063c06
 * Chems
 * ≈161-399
 * 15
 * ≈322-798
 * 40
 * ≈483-1197
 * 65
 * 79%
 * 3-7 Stimpaks †
 * Lucky Harith
 * 00063c08
 * Weapons & Ammunition
 * ≈161-399
 * 20
 * ≈322-798
 * 45
 * ≈483-1197
 * 70
 * 82%
 * Mini nuke
 * }
 * 70
 * 82%
 * Mini nuke
 * }

† depends on player's level