Lol well the safest way would to trade with positive people, those who have been members for a while and those who can be trusted. Simply put use a OMM for anyone you don't trust. To get rid of of quick and easy, and to make a pretty Pennie sell at a decent rate, eg .35-.45/mil depending on amount being bought. When selling via PayPal, make sure you have them send as a gift, and insert a note, stating it is for virtual goods and that they have accepted your TOS, and void any chargebacks that may occur. If a charge back does occur, simply call paypal, and explain it was for virtual goods, and that they agreed to your TOS, for the goods. Also I can't stress it enough but sell to trusted members and use OMMs for "non-trusted".
On a side note, if you are interested I can buy buy around 250m for around 75$ shoot me a pm and we can discuss.