According to
this thread, a newbie account cost .07 to start posting (due to a lot of units of evil).
Generally speaking you can sell a member account for between .03 and .06, a full member for between .11 and .25, a senior member for between .33 and .6, and a hero member for between .75 and 3.5; however the upper range of values for both senior and hero members are somewhat difficult to get.