I'm in the process of building up a (relatively small, by the standards here) 240G tank. The tank and sump came to ~$2000 including delivery. The wood for the stand was ~$900 (the cabinet doors were expensive). The pump (a reeflo dart gold), plumbing, and RO/DI system came to $1500. Fresh & salt-water storage tanks were another $550 inc delivery. The dosimeter pumps for automated water change and top-off were another $350, the lighting I'm doing myself with LED, and that'll come to ~$1000. I have an old skimmer, but I'll probably go for a bubble-king 200, so that's another $1500. That's about $8k before stocking... I'm doing a fair amount of the "building" (including an exceptionally cool reef controller not accounted for in the above) myself as well. This is not an inexpensive hobby...
Simon.