You were given the starting prize of the bid, that was the minimum bid we can place.

There is an option of buying the items directly without bidding for Diamonds.

As soon as you type the amount and place your bid you receive a message either if your bid is the higher or someone else bid higher than yours.

After the time runs out, if you were not the highest bidder you will get back 50% dollars from your bid or 70% if the bid was in Diamonds.

If you turns out to be the highest bidder the item will be yours.

You can Raise your bid; you pay the difference amount of your previous and new bid. eg. Your first bid was 1000$ and now you wish to increase the bid and wants to make it 5000$, you just have to enter the difference amount 5000$-1000$ = 4000$