Crumbling insulation ended with the 1988 240s. Some "patients" have been cured with either a new harness or rebuilding the old one. Not a tough job, only four wires needed, usually.

Vibration check: Get one front wheel off the ground, grasp wheel at 9-0'clock and 3-0'clock, rock wheel in a left turn / right turn fashion, and see if you discover any slack. If yes, a visual can poften see if slack is in tie rod ends, ball joints, or tie rod inner joints.

Next grasp wheel at 12-0'clock and 6-0'clock, rock it hard. Slack, and sometimes a "click", indicates looseness in wheel bearings.

Check both wheels.

Often vibration is result of a tire problem. Check tread wear for excess on inner edge or outer edge, and "cupping". Test drive after inflating to 32psi all around. Look at tire sizes, are they the same on each axle?

Consider telling seller that you are worried that car may need $1,000 to make it reasonably reliable as a commuter, and offer $300 (to get to a $1300 value).

Or check similar cars on ebaY for what the market might be.

Check for rust at lower windshield corner, and lower corners of 'way back windows and cargo door window. Also in cabin, above driver's left toe and passenger's right toe. If possible check under the front carpets next to the door sills.

Does the air blower work? Air circulation is a critical item for heater, and (here in Texas) air conditioning. Blower motor repair is a 5-hour job for me, and for a newbie we advise allowing ten. Part is about $65.

Good Luck,

Bob

:>)