If you bid for an item on Yahoo Auction Japan, then there will be 3 possible outcomes:
Outcome 1: No other bidder is bidding for that item
Outcome 2: There are bidder(s) with a lower price than you
Outcome 3: There are bidder(s) with a higher price than you
Outcome 1: No other bidder is bidding for that item
If you place a bid price higher than the starting price and no one else has joined the auction, then you will be the highest bidder. You pay for the bid price then the item is yours. Sometimes, you may win the listing item with the starting price.
Occasionally, the seller will set a “hidden minimum selling price (最低落札価格)”, which means the bid price has to be higher than the hidden minimum selling price, then it will be sold to you. If your bid price is lower than the hidden minimum selling price, the seller will not sell you the item, although you are the only and highest bidder. I know it may sound weird, but it does happen in this system.
Outcome 2: There are bidder(s) with a lower price than you
If you have a competitor, who bid at a price lower than you, then, the system will automatically increase your bid price on your behalf in order to continue bidding. Your bid will always be slightly more than the competitor from JPY10 ~ JPY1000.
Let’s say there is an item, with the starting bid price of JPY300. If your budget is JPY100,000, and you set the bid to JPY100,000.
Then,
If the competitor bids JPY500, then the system will set JPY510 for you.
If the competitor bids JPY1,000, then the system will set JPY1,100 for you.
If the competitor bids JPY5,000, then the system will set JPY5,250 for you.
If the competitor bids JPY10,000, then the system will set JPY10,500 for you.
If the competitor bids JPY50,000, then the system will set JPY51,000 for you.
As the winner, you will have to pay “a slightly higher” amount than the second highest bid. In most cases, you will win the auction with the amount lower than your maximum bid in the end. Occasionally, you have to pay the maximum amount you bid.
Outcome 3: There are bidder(s) with a higher price than you
In this case, you lose the bid.
Occasionally, when the winner is unable to pay the seller in time, then the second highest bidder will become the winning bidder and they will then receive a notification. In that case, the new winning bidder will have a chance to deal with the seller.