What kinds of chars get actually bought on trade?

Hi, I'm wondering if a fresh lvl 80 char on Icecrown would get bought and/or if it needs some boe equipped (how many?) to do so.
And about Blackrock, would a pretty geared char (6.3/6.4) be bought with all items equipped or with just main items?
Tryin' to understand how this market works, thanks in advance

Usually what people look for is max flying/2 professions/exalted northrend reps/some gold or boes, as long as it's cheap as possible.