This is a fairly common monocular student microscope with a nice pair of objective lenses:

Olympus Tokyo Microscope #356853 100x 40x w/light, box
(note: 54 characters will fit)

light source (note if it is Olympus--looks like it)

two objective lenses:
H1 100 1.65 (add Olympus numbers)
40, 0.65, 0.17

Olympus Tokyo wooden box

Before taking your auction pictures, wipe the microscope body and stage with a slightly damp cloth. (That green crud should wipe off.) Don't try to clean the lenses--leave that to the buyer. Dust or vacuum out the box, as needed. Fold the cord up neatly and secure it with a cord binder or twist tie.

Unless you can evaluate the working condition yourself, consider giving the buyer a money-back guarantee or working condition.

Google and Wikipedia are not substitutes for education or intelligence. —cornercube, 2009

There's a similar one listed for $70 (#380208759737) that has been listed previously.

The market is flat right now. I'd clean it up a bit and take some good photos. If it presented nicely, had a working light, and the box was attractive, $80-100 would be a reasonable estimate.

Google and Wikipedia are not substitutes for education or intelligence. —cornercube, 2009

You may be right about the eyepiece--initially I thought it was the angle but now I'm not sure.

This model only has two objectives. Take a look at the comparable (but do it quick, it's going to expire soon).

Google and Wikipedia are not substitutes for education or intelligence. —cornercube, 2009