NRG Control Amp A150S - Ballpark value?

Helping to simplify a household that's moving after the death of the techie -- can't find where to start with the sale of his NRG Control Amp Model A150S. Saw some discussion of it here. Can anyone give me a reasonable starting price? It works great, but the family is moving to a much smaller place and doesn't need so much high end a/v equipment. I can't seem to find a ballpark price anywhere.
Try the Orion Blue Book as a starting point. Or you could just throw it up on Ebay with a no reserve auction and find out it's actual value.
Thank you. I did try the Orion Blue Book first, but I was hoping to find a way to get the information without paying for it. In the end I paid the money. For anyone out there in the future: Original MSRP: $3,998.00 Current used market value 8/12/2012: $1059.11-1294.47; Current used trade-in value: Mint wholesale $236.71-289.31; avg wholesale $118.46-144.78
The best way to find out is to put it on auction, start at $1 it will go up as these were somewhat popular way back when.

Best of Luck

Did you ever sell this amp?