I\'m a weapons dealer. Here is my advice to you: Target the middle market. This means you should specialize in scorched weapons, icy weapons, and weapons of iron. Such weapons can sell in the 1,500 - 3,000 range, and there is a large market for them.
Compare that to the market above it: Fire, frosty, and dark weapons. These weapons are twice as powerful as icy and scorched, and icy and scorched are twice as powerful as iron, and iron is around five times as poweful as basic. These powerful weapons fetch prices from 6,000 tria to 10,000 tria, though I have bought such weapons for as low as 5,000 tria and I\'ve sold them for as much as 12,000 - 20,000. You would think that this would be the best market, but it\'s tiny. The weapons don\'t get sold or bought often. Most of the time, it\'s a more powerful player buying such weapons for newer players within a guild.
I have 18 such weapons, and I\'d have to spend a long, long time in the plaza before selling them all. Buy scortched and icy weapons for 1.5k and sell them for 3k, I really think it\'s worth trying. I can\'t switch over because of the inventory I\'m sitting on, and secondly because I already have a reputation for selling such weapons.