Id say price is about right, or a bit too high actually
I would guess 120k to be about right,
its 14 years old...
If its in mint condition, then perhaps its worth it, but then you got to be prepared to keep it...
Sold mine for around 120 about 2 years ago, miledge was about the same if memory serves, and my car was not "spotless", it was in neat condition, but not spotless.
Facelifts are going around the 140k mark.
But it is probably the best M5 BMW ever built, as long as the vanos is ok, gearbox ok, and the car has regular service intervals that can be proved....
Be prepared when you get it, to replace the crank bearings, as its a failure point on this motor, these can be done by simply "ok not simply" removing the sump and doing it from underneath, its not a "MASSIVE" job, but I would not trust just anybody to do this
Other then that, listen to the gearbox, syncro's go, and can go horribly wrong.
Clutch, flywheel...
if your really serious about this, and you want to be anal, ask the dealer if you can have a tiny bit of its oil, take it from the motor yourself and have it analyzed...
Discs are 2.5k a side when i last bought (3 years ago)
Rest of the car, is an E39, there are problems, GM5 module, window switches, bla bla bla, but its all easy stuff to fix.
keep in mind that its a performance car, its 14 years old, and not cheap to maintain, and little old ladies do not buy M5's to drive to church with and keep it for 14 years, so its more then likely had a hard life.
If you look past all of this, and can part with a 140k cash, and your prepared to do maintenance, they are EPIC....
On the drive, remember that its a sports car, not a comfy cruiser,
They make shit daily drivers... suspension too hard, seats too hard, fuel consumption 15l/100 mixed driving, small fuel tank...
something else to consider.
A well specced BMW 550i E60 in manual... they are around...