All of the above, depending on if used or new and so forth. Actually, I prefer to buy from other collectors or dealers that I know.
A, B, C. It just depends on the watch. If it has an in-house movement, I try not to go grey market.
All of the above plus trade/purchase from other collectors whenever opportunity occurs and the price is right..
Watch enthusiast and collector. There’s more to collecting than Rolex 👀😆🤷♂️, but Rolex hahaha! In all seriousness I collect what I like.