I believe dealers need to look very hard at who is extracting data from their DMS systems. There are a lot of vendors out there today that will visit a dealer with the idea of sending zip code driven leads to the dealer and the payment for the lead is made after the vehicle sells. In theory, this makes perfect sense, except for one little hiccup. In order to match the lead and the vehicle sold the vendor requests access to the dealership's sales data in the dealership DMS system.
From what I can tell here is the rub. The vendor then uses this aggregated data to in many cases publish transaction data for consumers. Transparency is a good thing, but the volume and accuracy of this data could and should be questioned by dealers. These consumer sites drive down already thin margins and even suggest to the public the price they shold pay,usually well below invoice.
So dealer's who believe they are getting better qualified leads, have now allowed vendors access to sales transactions to show consumers what they can expect to pay for a vehicle. A consumer left to his own site navigation usually does not get it right and rarely compare apples to apples. The other critical issue is the size of the sample. What if only a handful of vehicle have been sold recently by dealers who have granted access? My last thought is in a busy dealership everyone values their time and if the paperwork was presented to grant access during those buy times, dealers might not realize they have given the vendor access to sales transactions.