Product Page and Bid Page is the same page.
There is the Bid Page under the product page.
You write all places, you can start to bid. Another person also try to buy, if the product is good. So the price will be rise little by little. When the product is set the successful price, you can buy soon, but it depends on the seller. Seller can decide to set the successful price or not.
And the price is rise little by little, if many people want to buy.