There is the Adventurer's Mart in Waukeen's Promenade or the barkeep in the Copper Coronet or there is a Armourer/Fletcher in Waukeen's Promenade, a couple of levels 'up' from the adventurer's mart, or there is depending on where you are at in the game, the thieves guild in the docks district. These are all pretty much the same for selling items, but they do have different stuff to offer for sale.
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Never try to teach a pig to sing; it wastes your time and it annoys the pig
I've got to admit it's getting better, it's getting better all the time