Over the years I've done 46 transactions on Ebay with no problems at all. Yes, you have to be aware of scams, as you do in any part of life these days.
Same with Craig's List. You meet people only in public places, or you verify their information. You don't give out your own personal information. Just common sense. I've bought a couple of boats, some musical gear, a household item or two, etc. off Craig's List. Love it!
DonM