I've sold close to a dozen bikes in the past year. the majority were to friends or other moped folks thru facebook (groups not marketplace). All the bikes I've bought were through friends.
apart from friends I've sold 4 motorcycles and 6 or so mopeds, 1 moped was buy/sell here, 1 moped was on craigslist, the rest to friends via facebook or Instagram posts (not marketplace). all 4 motorcycles sold through facebook marketplace.
In the past 5 years I've bought 3 cars and sold 2. 1 car was a dealer, 1 I bought on craigslist, 1 was a facebook group (not marketplace). The cars I sold, 1 were craigslist, 1 facebook marketplace. I am absolutely forgetting some
Last house I rented we looked at maybe 7 places all via craigslist (5 years ago). Currently looking and it's 100% scams. Not a single legitimate listing. Facebook marketplace is equally useless,
For parts, everything I can comes from dos and treats, even if it's more expensive, cuz theyre better and it comes out better in the end. I used amazon until it was too obvious how immoral that is, really just their imbalnced attention to employees, and now it's mostly ebay or individual sites for rando lil junks