Then I will contact the second highest bidder. If you can't proof me that you have enough coins the moment the auction ends, I will also contact the second highest bidder. The reason for this is that if you speculate that the bitcoin price will rise, and only then have enough money to purchase the device, it's a definite loss for me:

1. Price goes up: I'm giving the device away for too little money -> Buyer wins, seller loses
2. Price goes down: I'm selling the device for more than it may be worth -> Seller wins, buyer loses

So as I said, if the price goes down, and you can't pay me, it's a definite loss for me.