why is your instant market value different for the same cars?

"At issue is the way CarGurus lists the prices of used vehicles on its website, including projected savings below market value and price drops. “… A savings claim or discount offer is prohibited except to advertise a new motor vehicle,” the DMV’s letter, obtained by F&I and Showroom, read, in part. “No person may advertise a savings claim or discount offer on used motor vehicles.” The Texas DMV Enforcement Division says that unless CarGurus removes the “offending advertisements” within 30 days, it will take action against dealerships with inventory listed on the site to the tune of $10,000 in administrative penalties each day a violation occurs, as well as other disciplinary actions."