Sure you can go it alone, but a wiser course might be to establish a relationship with a trusted dealer, particularly for more expensive pieces, and/or those where you need an expert’s eye.
To find pieces, dealers look in many of the same places you would on your own:
– eBay (I shudder to think how many saved searches they have),
– Chrono24, where private individuals in particular may have interesting pieces, and
– auctions worldwide.
If you have the ability to attend auctions, here you can get a firsthand look at dealers actively looking to purchase for clients or themselves. You might not know why a dealer is purchasing – sometimes it can be just to protect the price(s) of their existing inventory of the same/like pieces.
Beyond these “basics”, dealers have a number of advantages:
– will be contacted directly about pieces for sale by individuals (as well as other dealers) who may know of them from industry articles, social media, referrals, and so forth,
– may be a part of WhatsApp and other groups of dealers who regularly buy and sell pieces within their network,
– relationships with their existing clients looking to sell,
– “pickers” who find watches at estate sales, antique stores and the like, and
– retailers, who will see watches come in from an owner and then offer them out to a number of dealers, with the best offer winning the piece.