Speaking as a 240 owner, I'd say the low market value in many
areas comes down to these issues:
* Fuel economy. It's hard to find a four cylinder car that gets
less than 25 MPG, but you have to work to get a 240 automatic UP
to that figure. Our Camry weighs the same, has the same size
engine, automatic trans, and gets from 4 to 10 MPG more when driven
exactly the same way as the 240. That's *average*, not highway MPG.
* Reliability. This isn't what it sounds like, as 240s are no
more likely to break down than any other car of the same age.
What they ARE likely to do, however, is require very regular
preventative repairs (plastic radiator replacement, flame trap
service, throttle body cleaning, etc) that Japanese cars need
much less often. We've had the 240 for 6 years, and it's been
worked on at least as much as much as my 20 year old Civic Si.
Our '95 Camry, while not perfect, is a fuel-thrifty, reliable
*dream* in comparison.
* Glitches. Closely related to reliabilty, but not things that
disable, or threaten to disable, the car. The radios fail, the
seat heaters fail, the fan motors fail, the hood latches fail,
the tailights fill with water, etc.
* Age. They stopped making them in '93. I'd think twice about
buying a '93 *anything* in 2005, and most 240s are much older
than the '93's, not to mention less sophisticated.
So in short, the 240 is a tank. Like a tank it is rugged,
long-lived, great in a crash, bad on fuel, requires regular
(virtually monthly) maintainance, is fun to drive but not Sporty,
and isn't the best car for the typical, non-shade-tree-mechanic
driver. It's a niche car, with a devoted following.