A Max Bid is the highest amount you are willing to bid on an auction. This is a great option if you do not have time to monitor an auction carefully and would like to improve your chances of winning.
Your Max Bid won’t be displayed to other bidders, but will be used to outbid competing bids as they come in below your Max Bid amount. If you win, you will only pay the amount of the highest bid, not your Max Bid (unless your Max Bid ends up being the highest bid).