If you break your phone and you do not already have AC+ on it, you will not be offered AC+. You will pay the replacement cost of about $229 or possibly less if they repair it in-store.
Depends. I brought a shattered-screen iPhone 4s in for repair without AC+, about 9 months old if I recall. They offered to repair it, or I could get a $50 discount on the repair if I bought AC+ at the same time (or was it $50 off AC+? Either way, same outcome). Getting the repair and AC+ peace of mind for the next year+ was worth the extra $50, so I took it. AC+ coverage was effective the original purchase date (expired two years from original purchase, not from the actual purchase date of AC+), and that visit cost me more than had I bought AC+ day one (I think it was $250; had I bought AC+ when I had intended to when I got the phone and used the $49 replacement that would have totaled $150).
So, yeah, you might be able to buy AC+ when you need it, but it's going to cost more that way than just buying it up front.
IMHO, the minimum benefit AC+ allows is the option of new blank-slate hardware for cheap two years later. I have a 64MB 4S; replacing it for $49 at the end of this month with brand-new hardware before handing it off to the kids is tempting. I don't think there are any hardware or cosmetic issues to speak of with it, though, so I probably won't bother.
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I work for them and I cannot confirm that it is still $49 .
It is my understanding as well as my co-workers that it is increased to $79.00 across the board.
I wish I had better information, but as far as I know, it is now $79 per incident for everyone.
Sorry, but that would be violation of the AppleCare warrantee contract. It would not be legal for Apple to change the terms of the contract unilaterally.
The $79 fee can only apply to new contracts initiated after the terms were changed. Hopefully you aren't overcharging people coming into your store (ideally, the $49/$79 charge will just come up in the computer and store employees will have no say in it).