i recently had to use applecare for my mac pro. but it wasn't without a fight that i got what i wanted.
my mac pro was purchased in tokyo (
https://forums.macrumors.com/threads/423021/). i was living there at the time and about a year ago, i moved to canada. naturally, i brought everything with me. a while ago, my keyboard failed (
https://forums.macrumors.com/threads/682190/) and whilst trying to order a new keyboard by calling applecare, i was informed by the "specialist" that mac pro's are considered "non movable" and that moving the mac pro anywhere outside the country of purchase would render the applecare agreement void. needless to say, i asked to speak to his manager but only after i hung up the first time and carefully read the applecare agreement. now i know for a fact that this was untrue and called again.
they put me with somebody "higher up" and i confirmed my suspicions. applecare is VALID everywhere and anywhere with the exception that some parts may be available in one country whilst not another. even so, you'll get the "equivalent" or you can opt to pay the shipping to receive that part. a good example was my case where i had wanted the japanese keyboard but they didn't sell it in canada. i had them order it and ship it directly from japan at no cost for my troubles.
i can only suspect how many mac pro owners out there were stiffed by incompetent retards who can't respect themselves enough to do their jobs properly. applecare is valid without restriction and is, in my opinion, a very wise investment. i always consider the cost of applecare as part of the cost of the machine itself.
don't ever buy applecare on ebay. it's not legit. who would sell you something worth $300 for $100? it doesn't make any sense. in my opinion, many who support buying applecare on ebay either sell it themselves, know somebody who does, or just don't even know that their applecare agreement has already been cancelled.