My personal experience is 2 days at the track - over 500 cars so you need some time to see everything in the paddock. There are 5 major auctions durintg this week-end, -
Goodings, RM, Bonhams, Russo & Steele, and Mecum. There is the famous Italian Concorso on the Fri, and also the Quail Motorsports Gathering Fri. and the world famous Pebble Beach Concours Sunday.
The concours events are now pricey and even the auctions charge admission.
There used to be a very good Automobilia display/sale mid-week at the Marriott registration Hotel - not sure if that is still going.
Google up Vintage Motorsports for the calendar of events.
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