Scamming is aloud, unless it involves ranks. So if this person DOES provide screenshots and legit evidence, then action can be taken.
So if your scamming people on factions say selling kit admin for 1000 right. They pay and you just be right back home with the money and the kit. is this alowd?
That does not count. If it involves real money and ranks, it is ban worthy if there is enough evidence against them.
Basicly scamming is allowed if its not worth real money, but the reason it's allowed for you did it on your own action making it some thing you caused. Sure he scammed you but as xBMAN88 said you got to be careful on what you do with your money.