I don't want to even discuss what my reef tank costs. I'm running a minimum setup and just equipment, I'm over $500. I've got about $230 in test kits. Dead rock and live rock and sand came to over $300. And I don't have a skimmer or sump or refugium.
This is for a 45 gallon tank.
And everything has to be tracked constantly. For power compact lights, when six months is up, replace them. But the rewards... look in the photo thread for my latest tank pics (keep in mind that it's been going for six months now. It's not a instant thing.