Each one has a starting bid of $25.00 and an auto-buy of $50.00.
Reply to the correct comment (in order of 1 - 4) to bid.
Auction ends 8PM EST 4/21.
Auction continued by 30 minutes after last bid to keep people from sniping.
Auto-buy includes your choice of either a colored sketch bust or added clothing (limitations).
Once bought you own it entirely, and may resell it for higher, change whatever you want, etc.
Link
Vicious
Bid here for number 1.