London

IN the summer of 2012, Christian Bertermann was a frustrated young man trying to get rid of two old cars that belonged to his grandmother.

Mr Bertermann, 31, an Internet specialist in Berlin, had recently quit his job at Groupon Inc, and along with fellow entrepreneur Hakan Koc wanted to set up his own company. Spurred by Mr Bertermann's inability to find a dealership to both value and sell the vehicles, the men created an online business to fill the gap.