The difficulty with setting a price and then wanting more car is that you will get less car when you pay less for more.
These cars can always go another 100k unless they are rusting apart. I have a 91 420SEL here today with near 700,000miles on the lower end. One trans overhaul and two chain failures (the last near 250k ago - he now watches those rails religiously).
Bosch Master, ASE Master, L1
33 years MB technician