TL:DR
Just go to the Help button up there on the right. The drop down menu gives you the Resolution Centre.
You can file an Item Not As Described dispute.
Yes, you will have to return the item on your own dime, with Confirmation of Delivery. You will not be refunded your return postage.
If you were returning the phone to Future Shop, they wouldn't pay your busfare to to the store either. That's the way it goes.
If the seller does not refund you in full when you can prove that he has the phone back, Paypal will refund you and go after him for their money.
You don't need to talk to anyone. It's all automated. You just follow the steps.
Jayne, your mouth is talking. You might wanna look to that.-- Captain Malcolm Reynolds