The final remaining cars at a popular brand's factory site have been sold at auction for almost £80,000.Saab's Trollhättan factory in Sweden has sold the last cars remaining at the site at a ceremonial event that drew large crowds of enthusiasts.Several hundred people attended the conclusion of the auction of seven models from Saab and Nevs, with some enthusiasts travelling from the United States and across Europe.The Trollhättan factory sits ar…