As far as Armslist goes...I have sold about four gun there with good results. I took the chance and purchased two and got good deals (LNIB 681 ND 4" w/ brand new S&W holster for $600) Now I remember buying a model 627 after I checked the seller's bona fides.
My best deal have been at a local gun shop that is totally in the dark about revolver prices. I love them! They don't get too many S&W wheel guns in but when they do I am all over them. And the staff is friendly, good range. I hope it stays this way. They treat me great.
About four weeks ago I noticed a Colt Cobra 1st issue with carved grips. Consignment $595.00. Had them call the owner and got it for $500 plus tax etc. The grips must have been bought used somewhere. They were marked $15.00 on the back but they were honest to God Ivory. They were made for right hand carry and I am a lefty. Sold them last night for $950.00