I am writing about the sites where you have to make a deposit before buy and the site offers to act as a MM in deals.
How could I know when they are trying to scam me? In general, how do I know if a MM site is trusted?
Search on the web about the site you are joining,ask those who are already on that site for feedbacks.if you perform this two im pretty sure you will not get scammed by any hyip ,ponzi site.
But unfortunately a HYIP or ponzi will not last for long time so that some people may not have a track of site you might be looking for. How your friend will be helping you when you are going to join a brand new HYIP site. So, analyzing by ourselves must be the only possible way to protect ourselves from many future scams.
In the past Hyip had a sequence, that were the first members will be able to roi, since they will promote the website to others, that will invest, soo in the medium short time the admin stop paying, lets say 2-5 months, since some last even more, but nowadays they stop paying 3 weeks or 10 days after they get a lot investment, soo there is no way to prevent this kind of scam. People still get the ilusion of fast money without have to do anything. To protect your coins just avoid those ponzis, invest at trading, sport gambling or any other thing.