There are sites devoted to details of bidding on Priceline, most notably Bidding for Travel and Better Bidding. At one time, bidding through the US site from Germany meant creating an address from a drop-down menu of states, which meant Germany became Delaware (DE). Whether this is the case will be a matter of your own experiment. If you make an offer, you are buying whatever you get on the spot - same for Hotwire. Priceline may allow for purchase of cancellation insurance but there has to be a medically certified reason. Priceline has high standards in hotels and car rentals. But remember that they add on their own fee and taxes. So when you create your bid, look at what the total bill will be before you click to go to the next step. Also, for hotels you can only bid for a particular set of parameters once every 24 hours. You must change a parameter other than price to bid again within 24 hours. A field of scholarship on how to get around this has developed (called permutational bidding) and it is discussed in the boards devoted to the subject.