very nice stock 661 goes for 900-1000. Maybe 800 if your lucky. But you still don't know what you have. So you spend 40-50 to ship it off and 300 to port it. Then WAIT and WAIT. Hopefully nothing else needs fixed to make it right. This is is very nice. Ported and already gone through. No waiting and very likely cheaper than if you spent the time to go find a used one etc etc.
Very easy to spend $100 in "smalls" to make a saw "right". Seen plenty of good deal saws come into scott's shop having worn internals. seals, bearings, carb kits, lines, clutch drums, ...stupid stuff that adds up.