Thank you both for helping me. I have no idea on jewelry and weps so I needed some help!
Weapons - splinter/hit spell/HLD/HLA (antique and brittle will bring down value) value can be determined by what special moves the weapon has (AI, disarm, feint/Para are generally good.
Jewelry - FC/FCR/EP /DCI /HCI/SSI/DI/+skill (usually +15 or more in a skill) antique also lowers value (but can still be VERY valuable so don't worry as much on jewelry.
That should help you a little. Uo prices can be odd, sometimes I put a brace on a vendor and it sits there at 20m for 2 weeks. I can toss a relatively close brace on for double the price and it may sell in an hour. It's all about what people are playing for their templates. Always start high, some people will spend a lot for what they need.