The economy is heavily dominated by cash items. I could per-say spend a small amount such as 10 to 20$ and generate myself a pile of gold in that game.

Ex. Custom Accesories (Wing and such,) Are like 2-3k+ Gold. Eden Crystals 90-100g a pop.

However, you do not need to rely on the economy as much as you think for PVP. It is quite easy to get some gear for PVP, but being rich does fine-tine you to perfection in that game.