check that the seller has good feedback .... the higher the number of feedback ratings the more experienced a seller they most probably are. I wouldn't buy such an item from a new seller with little or no feedback.
Research the iBook you like and see what kind of inherent problems if any, it might have.
Does it come with original system install discs? While not essential, you will need to consider purchasing these as with any 2nd hand system, you're bound to need them.
What are the original machine specs compared to the specs of the one for sale on eBay ... are you buying a upgraded Mac, like, has there been more RAM added, or a larger HD, or any added bonuses ?? Don't worry about what software is installed as you shouldn't buy the Mac for the installed software IMHO.
Look at as many of this particular type of Mac as you can, on eBay, to see if you are paying a reasonable price. It helps to see what other people are selling and what they are asking.
Be aware of the terms and conditions .... read them carefully to see whether you are buying 'As Is' or if there is a 'DOA' clause.
Wrapping up, you should ask as many questions as possible. This also establishes a sort of rapport of sorts with the seller and you can gauge there attitude sometimes, which is certainly useful.
It is risky, but if you are careful you can pick up bargains.
Oh, I nearly forgot .... beware of what's known as
"Shill Bidding". To me, that's anyone bidding on the item that has 0 feedback next to their username. There are many occasions where the final price has been inflated due to these fake bidders pushing up real buyers bids ...
Finally, there's this:
Last-minute bidding
Placing a high bid in the closing seconds of an auction-style listing is called “sniping” within the eBay Community. Sniping is part of the eBay experience, and all bids placed before a listing ends are valid - even if they're placed one second before the listing ends.
To help avoid disappointment, ensure that the maximum bid you enter on the item page is the highest price that you're willing to pay. The eBay bidding system automatically increases your bid up to the maximum price you specify, so entering a higher maximum may help prevent you from being outbid in the closing seconds of a listing.
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