Bassically a shop/store on the waterfront with unique weapons with lots of benefits, they will be listed below along with all the changes made.

Its is located just behind where you go to start the Thieves Guild sidequest. (Shouldn't be too hard to find)

The weapons that are sold are either Daedric Artifacts or custom models of weapons with benefits such as increased damage and speed.

The shop is called "Items of Interest" and its sells:
A playable 'Amulet of Kings' with a 15% resist to normal weapons enchantment. (Amulet of Awoegi)
A ring with 100% chameleon enchantment. (This may be a cheat item but who cares) (Hobbit's Ring)
5K empty Black Soul Gems.
5 Soul Spheres (Azuras Star)

Weapons:
Arrows (Leaf-Bladed Arrow) 75 DMG + 5 speed
A Goblin Staff (Staff of Moses) (Has Hrormir's Icestaff's Enchantment)
A Staff of Worms (God's Wrath) (More charge than the orginal SoW)
An Akaviri Dai-Katana (Murasame Blade) - 160 DMG + 2 Speed
A Club (Jenny) - 100 DMG + 1.5 Speed
A Sanguine Rose with a Skull of Corruption Enchantment (Lilith's Rose) - 65K Charge
A Mace of Molag Bal (Amanda's Mace) - 250 DMG + 0.9 speed
A Volendrung (Divinial Seal) - 1K DMG + 0.3 speed (I felt a powerful weapon should be slow)
A Cutlass (Rose) - 110 DMG + 3 speed
Goldbrand
Wabbajack
Volendrung
Skull of Corruption
Sanguine Rose

and some more items but I'm not quite sure, Claymore of the Glacier I think (Glass Claymore).

If you have any questions please don't hesitate to ask (:

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How to install
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Simply unpack the .rar file into your Oblivion data folder and click the "Items of Interest" mod in the Data menu (: