What is It Worth? Used S600
 

Looking to buy S600 used, 128k miles.
I Took a video while I was there.

Cold starts just fine, a few seconds later drops to running only half engine OR limp mode. Can't tell since there's too much noise in engine bay.

when driving, have to floor the pedal to get it to move, at all. Had trouble backing over slight incline on gutter section of driveway.

Transmission coupler made clicking noise.
He says it throws Esp and transmission code, but wouldn't tell me what code even asked directly. The air suspension seemed to work, it was hard to tell but it moved up and down an inch with the button (could be leaking if I understand it should move more than that)

please note there is a clanking noise that could either be a bad piston bearing, OR the timing chain / guide is f@#$ed.

interior is 6/10. It road along well when we got it up to 20mph at least.

is it even worth $1000? My gut is saying walk away

Go with your gut Sir. If the seller wouldn't even be helpful in revealing the codes......then so be it and find a better car. GL.