IF they don't increase the amount what I did for multiple wigs was I made one listing for a few of them and in the description field I listed out the separate cost for each wig. You could try that.
2014 Convention Schedule-
ConnectiCon -Hartford CT July 11-13
Another Anime Con - Manchester NH October 17-19
~Cosplay 2014 Progress~
Jean!WoC -Attack on Titan 100% done!
Washu Hakubi - Tenchi Muyo! 100% done!
Motoko Kusanagi - GitS 0% (planning stages)