Arizona Error Quarter?

Can someone please explain in pics what to look for in the Arizona Error Quarter? What are they selling for? Are they only coming out of US Mint Bags or can you find them in rolls at your bank? I am thinking of getting 20 rolls of them to search at the bank. Thanks for your input in advance.
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A later die state (if that is the correct term, from gocoinsrusii's auction). These have been going for about $5 each:
And then finally the most desirable one... this has the cud from the second coin, and also a die chip between and on top of the "20" in the date. (Picture from kpl's auction). These have been going for up to $30 each:
Hope that helps!
Edit: Oh, and these are being found in the P-mint quarters.
But beware! These are minor errors not varieties. LOL
Here are three different ones that I have.
#1 has two extra cacti
#2 has one partially covering the designer's initials
#3 is plain, no die variations noted