I have lost Hugh amount of bitcoin, and I believe some person's here too have gone through same. Can we please share our experience and lessons.
if you are talking about scam
Yes one time i here deal with a guy from Vietnam , that was mys mistake i sent bitcoins first and he sent fake gift card and run away with my money never come back to the account.
i will suggest to use Escrow service,
if about trading scams
BE safe while trading never your private key of ether with any website of google forms , if any asks sure they will stole your coins from wallet.
never fall into trap who says this coin will be pumped or dumped ,they just make money by publicity noting else believe me
. and one thing this is alt-coin discussion section you cannot talk about bitcoins here move your post to bitcoin section or scam one