Player auctions will be easiest because they can't charge back with that. You could have them just send it as a gift but I would only suggest that if they are really trusted.
Yeah, you have to find a trusted user or use playerauction althought the fees are higher and you need to provide ID etc. Pm me if you want to sell the gold, I might be interested using PA or PP. You decide.
Even if you send as a gift they can still chargeback. I heard that PA is like the safest way to use paypal with since they have some protection guard system. Only accept straight paypal from trusted users that have a reputation in the market.