How does proxy (max) bidding work on government auctions?

You enter the most you are willing to pay, and the platform bids on your behalf in the smallest increments needed to keep you in the lead, up to that maximum. Other bidders see only the current high bid, not your maximum.

Proxy bidding is standard on GovDeals, Public Surplus and GovPlanet. If someone else's maximum is higher than yours, the platform outbids you automatically and you get a chance to raise it.

Set your maximum once, from your all-in budget after the buyer's premium, tax and transport, and leave it. Most platforms extend the auction when a late bid lands, so a last-second bid gains you little. On Public Surplus a proxy bid triggered in the last 5 minutes also extends the clock.