i think moe is short selling you, a new 617 will cost around $900...
in good condition with no scratches and the side plate and screws not marred, light drag marks on the cylinder and no obvious dings and just "honest" handling marks I would say around $650-$700
for heavily used, some scratches and maybe a ding on the edge of the sight rail on top, screws have been marred and the sideplate looks like it has been pried off with the bottlecap off a coors then I would go with what moe says $450-$550.
it also depends how quick you want to sell it.... being xmas I think you would sell it quick at the $500-$550 mark but at the higher price you would be waiting a week or three to move it.
this time of year I would also heavily discount it every BTT... to get it moving. Trade wise you should be able to go straight accross for a NIB glock or M&P or something of equal value.
