I found in order of importance:-
All this equipment will get you to Master level at which point you simply have to get some big guns as the tee boxes you play move back so far.
Putter (remember you will play more shots with this one club than any other single club in your back) - get the Spider as soon as you get to level 19 (from memory).
Iron Set. - Early on the Starter Plus clubs will get you a long way until you can afford a set of Raptures or K-15's.
Wedges - as expensive as you can afford and get three of them. I no longer carry a hybrid and carry three wedges instead - get you out of trouble all the time.
Driver - Rapture again - just so forgiving
3 Wood - rapture same as above.
Balls! - forget distance balls, you want feel, spin and accuracy, this game is all about touch not booming it down the middle. So get the balls that benefit 70% of your shots rather than distance stuff.
Hope it helps.
Oh, and I don't pay to play either, this is all bought by grinding out credits watching videos, answering surveys and beating all the sandbaggers on Blitz games.
Avoid Skins games until you have big gun equipment - you just won't be able to compete.