Facebook also does aggressively fuzzy searching. I was in the market for a sailboat last year, and knew pretty specifically what I wanted. Facebook would always be about 50% what my specific search term was, and then 50% barely related bullshit (wrong brand / size, sailing accessories, powerboats)

I've also found Facebook exceptionally flaky from both the seller and buyer side. I don't usually expect responses on half the stuff I'm interested in on Facebook, and it's almost impossible to even give stuff away with the flakiness of people actually showing up to pick it up.