When trading paypal you need to have a MM account which you can use to send funds to your real account, it makes scamming very difficult and you can make a PP account for $10
Which type of account is MM account, how does it works and when you said PP are you refering to paypal account?
A MM account is a middle man paypal account you use to receive the funds and send to your main account.
Middle man paypal account can be of your own i believe. You just create an account and use that to receive the funds and transfer to your main account so a charge back can not happen to lock your account. If it does then it happens to the MM account and that is a throw away account anyways since they can not trace it back to you.
^ Needs to read the post directly above before posting.