This is a pair of coaches that I worked on and are now surplus. One is a standard Colorado & Southern Observation and the other a Combine that became C&S.
$45 for either coach or $80 for the pair plus shipping. Paypal accepted.

Train Plant Rolling stock Track Vehicle

Train Plant Vehicle Rolling stock Track

Both have metal wheels, and I installed metal railing sets. Both have regular height couplers though they are still truck mounted. The Combine couplers are Bachmann mounted on top of the truck tongue; the Observation has a pair of USAT couplers which are a little smaller. They do couple together (pic below.)

Wood Fixture Gas Building Flooring

I added fall plates to the Observation, seams to the roof and I painted the clerestory sides green and the roof flat black.

Automotive design Automotive lighting Wood Hood Rectangle

Rectangle Grey Composite material Building material Automotive tire

Train Rolling stock Vehicle Track Railway

The lights, including the drumhead, worked when I tested them while the roof was off. I found a very old crusty 9V battery in the battery box whch had corroded away one contact so I soldered it back - I didn't check it worked! You might have to re-fix that.
Here's the underside and a truck on the Observation:

Building Window Automotive exterior Automotive lighting Gas

Motor vehicle Wood Font Rectangle Gas

No sign of wear on the wheels.

The combine was an experiment to try the Light Rail Products "duckbill" roof ends. They didn't fit well, but I managed to make it work. (Full thread on LSC about the build.)

Train Plant Window Vehicle Rolling stock

The metal wheels are solid, not the standard Bachmann plastic center/metal rim.

Ooops. I ran out of attachment allowances. Better add another post. . .