All I ever said was it would be prudent to spell out it is online only to avoid confusion. Nobody is suggesting you are offering full legal terms and conditions. I'm just suggesting how you can be more helpful to people, no need to get defensive.
AppleCare does go with the machine. The student warranty probably does as well (again, there is confusion) but a buyer is going to want to see "x months of applecare left" not "x months of student warranty left". So yes, may be good to add applecare if you think you will sell it on.
Whilst I appreciate that in the UK we get 3 years warranty on Education Store purchases (without going into the nuts n' bolts of it) I would still buy the Applecare - it's generously discounted to £46.00 with the student discount. The reason I personally recommend this is some Apple employee's seem themselves confused by the Education Store warranty and it just makes things simple in the future should you get a problem.