Already covered in their T&Cs
Not really. Those terms have been copied from their website, they should have been changed for Ebay use, why?
The conclusion of a contract between you and us will take place when we (i) debit your credit or debit card
Payment of the listing was by Paypal, Paypal is automatic in that you do not wait for the Seller to take the payment from you, once you have clicked buy it now or won the auction you then send instant payment for the goods.
They put the wrong price, its not really that easy to make mistakes on price because to add listings you have to go through their process and get plenty of time to edit listings etc, this is human error and/or laziness/ignorance when the wrong wasnt put right.