I would say this is related to the platform you're trading on. Certain websites exchange RuneScape Gold with players like garbage collectors. However, when they sell them to players at a different cost that isn't acceptable for me. Therefore, you must choose a reliable platform in the event that you do, you'll suffer quite a bit.
I generally prefer trading RSGold through the RSorder.com website, in part due to the fact that no matter what it is it is priced fair and transparent, and in line with the market prices. Also, they have a great friendly and helpful customer service. When I sold just OSRS Gold at RSorder, the customer service was also enthusiasticand they have would like to get OSRS Gold in the hands of players. This is due to security of your account, RSorder only trade items made available online by genuine players as well as OSRS Gold. This means that players can be at ease buying OSRS Gold.