Love this forum - just spoke to a another chap who was recommended to me by a fellow collector. He offered straight up a deal to service multiple watches. He pointed out that some may need no work at all if they have been stored depending on state of lubrication. Suggested an inspection and service every 5-7 years if worn regularly assuming no issues. Did remark that parts for some movements were becoming extremely tough to source so a service where parts are required has to allow for time spent locating spares. Much tougher for those remote from Europe.