The 409's have been going up as more of them come out of the closet. The price is about as expected for an average condition gun. The auction sights have been geting around a $1000 dollars for an unmolested 409 SxS. They were sound old shotguns and with care will be around for the next generation. The interest on 12ga is less than on the small bore 20ga and 16ga. They command twice the blue book prices and don't hang around long. Most of the older SxSs were hard finished. The higher grades had more oil finishes but only on request.
Best,
Ron