Three Brothers Trade Goods
Three Brothers Trade Goods is a general goods store located in the Imperial City's Market District. It is found across the street from The Merchants Inn and next to the Black Horse Courier and Jensine's "Good as New" Merchandise
The store is jointly run by brothers Tertullian and Sergius Verus. The third brother, Cicero, only lives there when not doing duties for The Black Horse Courier.
Tertullian has 1000 gold and a Mercantile skill of 60. When bartering, he will buy anything from you while only selling a variety of miscellaneous items and the unique Helm of the Deep Delver, which drains your speed while giving you resist poison and disease as well as casting a light spell.
Sergius also has 1000 gold and a Mercantile skill of 60. Like his brother, when bartering, Sergius will buy everything from you while only selling a variety of miscellaneous items and the unique Akaviri Sunderblade, which has disintegrate weapon and armor effects. He also sells all of the upgrades for your waterfront shack for a base price of 400 gold.
Three Brothers Trade Goods is divided into three areas: Three Brothers Trade Goods, Three Brothers Trade Goods Private Quarters and Three Brothers Trade Goods Basement.
The main trading room is located on the ground floor and consists of a counter and a selection of the vendor's wares on display. It's not exactly inviting, as the brothers seemingly lack any sense of arrangement: Chairs are piled up on each other and there's a messy corner filled with food, barrels and sacks. Opposite the front door is a table with a piece of cloth and assorted gardening and mining tools. A barrel next to the table contains the same. The table in the northeastern corner holds a basket with seven ears of corn. Behind it sits two pumpkins and a head of lettuce with an additional three heads hidden in the basket. There are two open sacks, both containing food, and three closed ones with clutter. The barrel to the right has a chance of a repair hammer and some gold, while the other barrel only holds clutter.
Next to the front door is a small table with various clothing: A pair of blacksmith's pants and a green wool shirt along with four pairs of shoes: buckled shoes, stitched leather shoes, rough leather shoes and clogs. The cupboard near the bottom of the stairs only contains clutter. The counter displays various kitchen utensils and behind them are three lockpicks and a few more rolls of cloth. The lectern only holds randomly chosen writing materials, while a mysterious note implies that one of the brothers might have a secret love affair, and a handbill suggests where they stock up on alchemical ingredients. Behind the counter are a barrel and a cupboard with clutter.
Elder Scrolls Wikia entry on this location can be found here.