Not sure how you are getting $25? Listia sells them for 10 cent each, so 100 * .10 = $10 not $25. BUT in reality listia values credits at 1/100th of a cent (read the rules in the fine print, it is in there). So based on that it's only 1 cent and shipping is FREE!!! WOW what a deal!
Okay, it's actually under "TERMS" and the bottom on the page.
6. Credit Accounts When you win an auction, your winning bid amount in credits will be subtracted from your credit account. When a user wins your auction, you get the winning bid amount in credits added to your credit account. Credits may also be purchased for a fee from Site. Credits have a cash value of 1/100th of one cent. Listia reserves the right to change the cash or exchange value of credits at any time without prior notice and without any compensation to members with existing credits.