I have been scammed on ebay. What do I do?

I recently purchased a brand new unlocked iphone 5 for 599.99. The listing said that there was a 14 day money back guarantee so I felt safe about the buy. However, 3 days later when the package arrived to my door, I was disappointed to find that the only contents of the box was a 3/4 full opened bottle of water.

I've opened a case with Ebay and Paypal. I also filed a case with American Express.
They said I wouldn't be charged for this purchase until the investigation ends, but how can I prove that I received a bottle of water in place of a 600$ purchase? The only thing I could think of was to take a picture as soon as I opened it.

What do I do?

How long should I keep my damaged iphone in white rice?

I dropped it in water, and at the time when I did drop it, it was turned on. So I picked it up out of the water, quickly got a paper towel to dry it off, turned it off for a little bit, then I tried to turn it back on to see if it would work, and it didn't. So I turned it back off, my dad went to the store to get white rice, and now it's soaking in it. How long should I let it sit there?

Uploading a DVD onto and iPhone 4S?

Okay so I've recently done a skydive and got a video of me doing it. I've just received the DVD of it. Is there a way to upload onto the computer then put it onto my iPhone?

Do iPhone 5 devices come pre-loaded with the latest firmware (IOS 6.1.3)?

I went to AT&T store just recently and got an iPhone 5 (I took it back… Don't judge me), and when they activated it, I'm not sure how but it already had 6.1.3. (Which I do not want.) I'm now wondering if all iPhone 5 devices come pre-loaded with the latest firmware. Or if that is just with places like AT&T and Radioshack. If not I want to try to go to Walmart if that will make a difference. I'm starting to feel like they just push it through. But I prefer not to have the latest update… (if possible).
so let me know…

IPhone T-Mobile Pay as you go?

I know t-mobile has the iphone now. I know they have a pay as you goish thing. Like i have to buy a card to add time/data.something like that. Its been a while.anyways, Is there a plan like that available for it? Or is this just wishful thinking on my part?

I got a refund for an item on eBay?

And I received the refund on PayPal but I bought it with my debit card and when I checked my chase debit card (on my iPhone app) there's no payment received though it was received back to me according to PayPal. Where was the money refunded to?