Why is the 407 used so cheap???

Whether it’s a limo, a station wagon or a coupe, it doesn’t really matter so far, whether it’s diesel or gasoline. 200 hp plus x and automatic have to be. Once, the small diesel with automatic was in Septmeber 2007 with 135 hp. And even though it was traveling with cruise control on Swiss motorways, it was a drunk in front of the Lord, as I find it (on average 8 l / 100 km). For the small diesel at any rate too much, at the Kind of movement. Basta! But in general: Why only do you get so much car for the money with the used 407ers??? Where is the catch? P.S.: the back bench probably doesn’t even exist with seat heating, does it?