iPhone AppleCare question

I'm looking to get the iPhone AppleCare for my girlfriends 3g iPhone. I've seen a bunch on Amazon and Ebay for $30-40. Is there any problem with buying it that way, with it being so much cheaper? I seem to remember when I activated it for my 3Gs that it says you need to keep your receipt. Will Apple deny coverage if it wasn't bought through certain stores?

Nothing wrong with it as long as it's truly an unused AppleCare code. I've done that before for my Macs. Amazon.com often has them pretty cheap too.

Did you ever have to make a warranty claim while under the extended period?

Yep, I had to have a logic board replaced once on my Macbook.

Apple has no clue where you bought AppleCare from, they just know whether it's a valid code or not when you register. You could have bought it off a bum off the street or from an Apple Store, to them it's all the same.

How can you know for sure it's an unused Apple Care code?

You do not and that is the catch.

Bogus sellers have a dozen and one tricks. Make sure you purchase the sealed box and not just a key code.

http://reviews.ebay.com.au/How-to-spot-FAKE-AppleCare-MUST-READ_W0QQugidZ10000000013594494

Thank you, harryb2448, I appreciate your response!