Picked up a second hand watch that had been serviced by a grey agent with no idea. My advice “don’t do it” On the bright side I will have a like new watch returned with a full 2 year warranty ...
why would someone buy an expensive and delicate piece and cheap-out on servicing it? I am on your side, take the hit for service now and enjoy your "like-new" watch.
My eyes cry seeing beautiful old APs listed for sale that clearly were polished outside of AP walls (so easy to tell). I only imagine the same guys trying to service a movement and I cringe.
Since it was a "vintage" RO, it had to go back to it's birth place for a service. Cost of service was about usd6000, from the papers i think 70% of the movement was replaced. No WR warranty though, since it's vintage. Repair took bout 8-9months.