I’m thinking of buying a used (2005) JLC from Watchfinder. It is a watch with a complication.
When I enquired about service history they told me the watch has been to their Madrid service centra, which is a Richemont facility( and is certified for JLC) to be "regulated". My question what do they actually do to the watch and how does it compare to a service? The watch comes with a 2-year warranty should issues occur.

Thank you in advance for your replies.

Two questions for the finance experts out there. I think they might be helpful for all of us when negotiating deals.
If I sell a watch to a dealer (straight cash deal) do they pay VAT when they re-sell?
If I do a straight swap, brand new watch for used watch (official dealer), where no cash has changed hands is the dealer liable for VAT on either the new watch or when they re-sell?
VAT, at 20%, is a massive chunk of purchase price. Would be good to understand this.

Thanks, SubDay