[Scan-DC] How to scan for auctioneers wireless audio?

[J. Andy Schelz]

Hi,
I hope someone can help me from your group, as I don't know much about this.
I go to a lot of auctions where the auctioneer uses a wireless microphone system. Most of these auctions take place over many hours, during which I am only interested in a few items that are separated by many items I don't want.
I would like to be able to scan their broadcast from my car which would be located outside the building. I believe that most of them use a UHF system (some may have VHF...I don't know).
Can anyone steer me toward a system that would work on all or most of their systems?
Thank you for your time,
Andy