A2000 for sale
The $1400-1500 range would be perfectly reasonable for your machine.
One thing to remember is that while advertising on Compuserve will get you
the best response, it will not usually get you the best price. For a
variety of reasons, new and used computers are less expensive along the
coasts of the US than in the middle. Since most CIS users are coastal (and
due to the laws of economics) CIS prices tend to fall at the low end.
If you know of a big Amiga BBS in Missouri or something, advertise stuff
there, and I bet you'll get a better price – IF you can sell it at all. The
advantage of CIS is a massive audience, not price point.
But you seem to be asking a fair price for your computer.