Facebook does have the Marketplace, which is supposed to be a local thing, but it is nationwide. Also on Facebook are a number of golf sites to join, some huge, some small, but mostly members of 1 are members of all. Unless it's a clique-ish type...the type that spend a ton, and have the same handicaps as their bank accounts. I've sold a lot there; clamps sold out in hours when posted the 1st 3-4 times. no complaints from anyone either, unlike what would happen on Ebay.
Prices have to be right, but sometimes can be way high for certain brand names. Components(heads/built clubs) are not a big seller at all, and get very little response. Shafts do well as do grips.
This is the only forum I'd buy/sell on/do buy/sell on.
Never used Craigslist, never will. From all I've read it is more of a scammer's market.
At this point in life, I'll trust no other sites.
If a site doesn't have Paypal as it's required method, I'd be doubly worried.