Overbidding has guaranteed downside. Underbidding has non-guaranteed upside. It’s pretty clear that if you’re playing an iterated game then you always underbid.

Overbidding has guaranteed downside. Underbidding has non-guaranteed upside. It’s pretty clear that if you’re playing an iterated game then you always underbid. Of course it’s a different story if it’s a unique item that you really want.