I buy lots of stuff on Craiglist, but I’m not sure I’d ever buy major appliances, although I usually look around there.
Major appliances are known to have little things that need tweaking (and not just once) or even major breakdowns or defects, and you definitely want to have the manufacturer’s warranty in place.
If you buy at Pacific Sales (and maybe other local retailers do this, too), they add another 4 yrs on to the manufacturer’s warranty with their additional service warranty (covers all parts and labor) for a very reasonable price. It was $177 for the extra warranty my GE Monogram fridge, which is almost the cost of a single service visit. I’m not one to normally buy extra warranties, but this one was way worth it.