I’m CORNfused

[Lynn]

Technically you CAN take a deduction for the amount you spend over and above FMV.
But it is a slippery slope, as you must be able to document that you KNEW the value before you bid if you are audited. Without a "qualified appraisal" you are in an uphill battle with the IRS.
If you are just sitting in the audience liquored up and decide to start bidding, thinking you can deduct the entire amount, you are likely screwed.