You may need to purchase planks for player-owned ports. Players may want to improve their building abilities. You may want to purchase bolts and RS gold arrows for the new ranged slayer dungeon. These are only a few examples of how you can benefit from these updates. Understanding graphs requires some time. While it may sound easy to know when is the best time to purchase an item and when it should be sold, it can take a lot of time to learn this ability.
I believe that investing is worthwhile. It is the way I earn my money. It isn't always risk-free however, most of the time the risky investments are buy RuneScape gold those which yield the highest profit. It is true that it works! I hope this helps.