I just added my first fish today, 120 galwith sump.Coast of set up in Canadian dollars. I bought to top of the line stuff from what I read, books are exter. This is for a reef setup, with SPS corals

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Sump 200 ( next time go bigger)
tank stand( DIY, Maple wood ) 500
skimmer and pump 600
return pump 200
heater 30
plumming(overkill) 150
live rock ( fully curded) 900
sand (one bag of LS) 90
lights metal halide two pendents 1250
flurorescents 250
LED night light 60
fans for cooling 60
R/O DI unit 300
test kits 100
refractor 65
monitors/ controllers 450
power bar 25
auto top up freashwater 200 + tank to put it in 10
phosphate and carbon reactor 150
refugrium in sump (DIY) 10
light of refugrium 45
tunze wave box (still to come and move wave makers) 600+(650 down the road_
clean up crew (need more) 100
first fish 200
total = more to come and pricelless joy meet.
I started one and a half years ago peascing the set up together. I set finnacel goals, like paying off X munber of dollars on the monage or bills. One piesce at a time.
Look on Ebay for complet setups, will save up money, and you know it worked for them.