Police suspect a professional gang of car thieves were responsible for a raid on Robinsons Group which netted seven cars.
Its dealership in Lowestoft was targeted overnight on Sunday and five Volkswagens, an Audi and a Seat were stolen.
Five of the cars were later recovered nearby but police are still searching for a black Audi A3, registration AO59 FHD and a VW Passat, registration AO59 UYY.
Robinsons, which has 15 dealerships across East Anglia, has put its other sites on alert to the thieves.
Andrew McCrostie, general manager of the Lowestoft branch, told the Eastern Daily Press: "The police said the security system we have here is very robust.
“It looks like a professional gang have done this and we are taking steps to make sure that it won't happen again.”
McCrostie also praised diligent members of staff who worked with officers to track down the cars that had been stolen.