I looked online and saw one for 25, so I say 25!
I wouldn't trust ebay though.
What people do is buy the game, take the serial from the book and seal the game case and claim it as brand new not opened.
Then when you come to play online the serial wont work. It's a way lots of people get loads of serials and can sell them cheap.
I think lowest new would be $40-50.
And used maybe $35.
It's on sale at Target for $47.
In Australia atm in stores its above $100...its shocking
find one used on ebay maybe,just be careful buying physical items online it can cause many problems
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Ya Ebay is a good choice
Black ops is priced around 60 for a new one.
Sams Club has them for really low prices if your a member
My local EB Games is doing a really nice deal, they halved most of the big name games this year.
BO was 40
Reach was 30
Red Dead was 20
ME2 was 20
This is Australian dollars btw.