[Reefiez]

The best advice would be to work backwards from the livestock you MUST have. Ie, fish that needs large tank? SPS corals? If you're not sure at the moment, taking some time to think about it will be best, or you will end up spending double or triple the budget on "upgrades" that could have been avoided in the first place.

well, the budget is a good one, I had some fun on the BRS website, here's what I got:

Tank: RS reefer deluxe XL 425 (black) = $2679
Lights: N/A (deluxe tank includes hydra 26HDs, and should be good enough for easy corals)
Pump: Ecotech Vectra S1 = $275
Powerhead: 3k ICECAP gyre + controller = $150
Skimmer: Reef Octopus classic 202 8" = $375
Refugium light: Kessil H80 = $129
Heater: Finnex 300w = $42

Rock: BRS Pukani 60lb = $227
Sand: Caribsea Fiji Pink (2x20lb) = $78
Salt: Red Sea Salt (blue bucket 175g) = $73
RO/DI: BRS 6 stage (Basic) = $230
Test Kit: Red Sea Marine Care = $48 (ammonia, nitrite, nitrate, ph, kh should be enough for softies with regular water change)
Refractometer: BRS refractomter = $40

For a grand total of $4346

Missing:
Mixing solution: i think brute bins are pretty popular
Refugium: gonna have to find a way to add a baffle in your sump area
Livestock: can't comment on that

My biggest regret, was not waiting 4 months for the red sea reefer XXL to come out lol! I am of the go big or go home mentality =)

Good luck!