I thought I would share, I think it's a decent blue-print for anyone who doesn't have a consistent income to feed this very addictive hobby.
-I have an "emergency" $1000 cushion that I will not allow myself to spend unless a PC card that will never show up again (most likely a 1/1) has surfaced.
If I ever have to spend a part of that $1000, I may not buy any more cards until I re-fill the "emergency" fund back to $1000.
-Any time a card I need for the PC becomes available, look to trade for it or sell other cards before buying it. It sounds fairly straightforward, but it's a good way to make spending money (when it becomes available) last.
-Prioritize every card you are targeting for your PC. You will regret it otherwise; trust me.
-If you enjoy busting wax, decide when and how much money is spent. Make this as consistent as possible. You have very little control over when a PC card will show up, so pick a time when you know you have money to spend every few months, year, etc.
-Have one "investment" card at a time if you are confident that you can make successful investments. Whatever profit you make, sink into the PC. Re-invest the original money. Rinse and repeat.
That's off the top of my head, would love it if other people contributed their advice/strategy.