Batgirl is typically under-ordered, so completists who want the entire line of books will be after that Batgirl #13, so I expect them to be $9-$15 or more pretty quickly.
Indy's Comic Pressing Submission Form - http://tinyurl.com/zbadtyy
Indy's CGC Comic Gradings Master Thread - http://tinyurl.com/p45agbh
Indy's CGC 9.8 Subscription Service - http://tinyurl.com/nnn6mhf
Indy's Tip Jar - http://paypal.me/thanksindy