Paintball = Money
I don't mean that equipment counts for all, we all know its a combination of each significant factor to bring a player up to his or her best. You can't shoot a Stingray fast and you can't break to a front bunker by walking.
Manning and KillerO make some excellent points. They can be boiled down to a list I'm currently having to live by:
Buy the least-
Don't buy anything but paint, and only if it's field paint only, at the field; build a good kit but don't keep upgrading unnecessarily or because of looks/trends); I won't buy anything until something is broken or my field role requires adjustments
Spend as little as possible on paint-
Local sponserships, reffing for paint, cleaning a local paintball store for discounts
Take a shot at major sponserships, it works
Have a set practice plan that alternates shooting and non-shooting drills (I believe in range work but also know that movement drills and exiting/entering bunker drills are also important)
Determine your tournaments and budget-
I missed an awesome 5-man last weekend that my team was invited to play either solo or with our partner team, but we didn't budget for it and times are tough (especially as we'd just played a ten-man and a scenario game back to back).
Okay, here comes the preaching. Get a job. Get a better job. Don't screw up at your better job to lose it. Get your spouse / partner / mate in on your paintball buying decisions so they can't jump all over you. (I'm not sure I do all those well, but I try.)
(Yes, I've got a good job as an IT analyst for an insurance company, but I also have a mortgage, truck payment and very forgiving family to make sure are financially looked after).
And most of all, priorities. Sacrifice (as was already mentioned) and dedication do it. I am looking at my own budgets right now and will probably spend more hours doing knee and superman slides in my backyard then opening up with markers all over someone's bunker for the next few weeks to save up for the next ten man. I'll still go to practices but I'll do drills, coaching and analysis more than scrimmaging.
Mostly repeating what others said, but they're dead on, gotta sacrifice to make it,
Larry