Grand exchange to do RuneScape Gold business is the core of Runescape, which is easy to control.
What you should do is to bring items bought with RS Gold you wish to sell or money to buy what you want. Talk to the one you’d wish to make a RS Gold deal and bargain with him. The clerks will take your items or RuneScape Money and look for a matching bid/sale to match you up with. You can wait your bid for RuneScape Power Leveling to be accepted and then for a buyer. Once the trade is over, you will receive a message. Then you may get your RuneScape Money or items in the Grand Exchange.
You needn’t keep logged in nor be at the Grand Exchange to Buy RuneScape Gold or the bank because the Rand Exchange for runescape power leveling will keep open all the time and the clerks will keep finding a RS Gold buyer or seller for you. You can go off and work on your skills, play through a quest or anything else you enjoy doing, and just wait for the message from the Grand Exchange!
You cannot buy or sell untradeable items and RuneScape Gold using the Grand Exchange and there is a small handful of tradable items purchased with Cheap RuneScape Gold that cannot be bought or sold on the Grand Exchange.
The business of RuneScape Power Leveling that Grand Exchange manages is all between players. This system will not destroy nor steal your items and runescape money, just transfer. So do not worry about it. Your offer to buy or sell will, therefore, only be completed if the Grand Exchange clerks can find another player to match your trade with. You will not know who you have bought items or RS Gold from or sold them to.