How to merchant with the grand exchange on runescape?

i have 1.5mill on 1 account

7.5m on the other accountHow to merchant with the grand exchange on runescape?
To merc is to buy stuff low and sell high. As for what to merc, you'll have to find that out yourself. Most mercs are tight lipped about that (myself included) because once you start doing it, you might ruin the market for them.How to merchant with the grand exchange on runescape?
buy low sell high.
I have 1 mill but never play anymore. I suggest buying expensive things when the price goes down and selling them when the price goes up.