Well, that's a large question on a 30+ year-old car...

Nevertheless, along with many other folks, I think the 71e is the best of the 140 lot and the most desirable one to own.

When sizing one up, the usual guidlines apply concerning body, paint, interior, and drivetrain. Some of the weaker points of the car that would influence any assessment I might make include: rust in exterior body seams and inner trunk wells, water leaks into the passenger compartment from inner body seams, worn front (A-arm) and rear-end suspension bushings and steering joints, cracked and deteriorated rubber body gaskets and seals, flat cam lobes, and some really ugly original paint colors. These are costly and/or time consuming to repair and remedy. Less costly to repair, but annoying common problems in the 140e are rusted out exhausts, bad air slide valves (fuel injection), screaming heater fan motors, unglued wing window latches and pivots, worn out clutch cables (frayed inside and stiff to operate), rotted inner door panels and unsealed door cavities, out-of-round rear shock mounts, and poorly sealed (moldy and barely opaqe) tail and marker-light lenses.

If the one you are looking at is relatively free of the above-mentioned problems, it has indeed been well-maintained and should be considered a good buy!
Matthew