zlacker

One would think that the auctioneer would benefit from maximal disclosure, as the present situation as you describe it is precisely that portrayed in Akerlof's "The Market for Lemons":

<https://en.wikipedia.org/wiki/The_Market_for_Lemons>

Moreover, many states require regular smog checks, at least on passenger vehicles (though I'm not sure what the situation is for commercial vehicles). These entail a comprehensive electronic data record, much of which is automatically captured from the vehicle, and which is available for sale. Auto insurance companies have used these data for years, if not decades, to set policy rates as miles driven is a principle driver (ahem) of risk.

If VINs are avaiable for the vehicles being auctioned, it's possible that a service such as CARFAX might carry such data. I suspect bulk / corporate buyers would tend to have access to such information, whilst small-time operators / individuals likely would not, which throws an additional bias into such auctions.

>>dredmo+(OP)
The auctioneer knowingly keeping a secret that could cause a downturn in the market once discovered and publicized in years and in the meantime keeping a giant client sounds very rational.

>>HWR_14+t9
It's a short-term optimisation which severely discounts future reputational and legal costs and consequences.

Though, yes, reality tends to be messier than economist's idealised models.

>>HWR_14+t9
Auctioneers would simply have a standard practice with respect to disclosure to protect their reputation, not keeping secrets. I know of none that advertise that they use a computer to verify the mileage/hours on equipment - if one did I am sure they would advertise it and be religious about its execution.