Can someone make a guide for item values?

I don’t know enough about trading to do this.

Can someone make a guide for item values? It would list all of the commonly traded items (boss drops, sunkens, headlesses) and have some information on their worth (i.e. You can trade a clean or strong sunken sword for a headless). It would be easy to link to and quote when someone makes an awful trade.

Ok,

Legendary+Seasonal > Epic > Rare > Uncommon > Common

This does not apply to fish

Thank you very much