Stand - Build your own from 1x4s if you're handy. 2x4s if you're not handy.
Filtration - 40 breeder sump made from Petco 1$/gallon sale. Use local glass shop to cut baffles for you.
Rocks - Dry rock
Lighting - Black box LEDs
Maybe it goes without saying, but get your own RODI unit.
Absolutely agree with the above quote.
Areas to buy good
used items:
TANK, ppl constantly getting OUT of the hobby daily bc of job loss or lack of time/interest. Search Craigslist BUT many ppl think their precious tank is worth 3x-4x what you should pay. A 6ft used 180g i wouldn't pay more than $400 for. A brand new one is roughly $1500. Many ppl want $1k for their used tank where a brand new one is only $500 more. 75% return on their investment? They're crazy cracksmokers. $300-$400 is what its worth. ALSO! When buying a used tank, I wouldn't buy it unless I saw it fully topped off with water. If they are selling a dry tank, they need to fill it with a garden hose in their garage..Inspect all the silicone seams running your fingertip along every seam. All because...Once you drive away with it, its yours. Sale is final. Even the police won't investigate if you got tricked into a lemon bc the police don't have time to investigate a fraudulent sale. Hiring a dang Lawyer is $2k MINIMUM
STAND, I like the idea of building your own stand to your height preference BUT what a "Pain-In-The you know what" sourcing material, measuring, cutting, building. In the end, it LOOKS like a second hand hack job unless you are a skilled Carpenter. Otherwise,try and COMBO a Craigslist tank with the stand.
PLUMBING, do your own plumbing. Its really not hard to measure, cut and glue (using both purple/white pvc cement). If you screw up is not a huge $ waste to scrap that screw up and redo.
CORALS! buy/trade from local reefers that are growing out corals just to offset their yearly expenses, like salt, etc. Online vendors and these R2R Sales (if you call paying $60 for a 2" acro or $40 for a 2polyp zoa a "sale") plaaaaaleeeze. You save so much more money buying 90% of all your corals if you can find ppl selling corals out of their basement. Sometimes LFS have a "Clearance" coral section where ciral just haven't sold for at least 6mos and they just want the corals gone. But if you buy from most Online Vendors, you will pay top doggy dollar. I like Online Vendors for stuff you can't find anywhere else but I also know I'm paying a premium to buy it. Example: bought a fully loaded plug full of Rasta zoas from a local guy for $30 cash. That same frag Online would have been 3x that price, no doubt.
Things you
should NOT go cheap on and just buy new!!
SKIMMER, the heart and soul of your ecosystem. It has to be rated properly for your total water volume. Don't go cheap here.
RETURN PUMP, buy a great rated one and it will last you 10+ yrs. Truly a "you get what you pay for" item. I'd rather buy a great return pump and not have to worry about it for 10yrs than a average one that I'm replacing every 5yrs.
LIGHTING, again you get what you pay for. AI Prime and Noopysche have fully timeable adjustable LED lights that are priced great for what you get. Chinese black boxes
burn up in 3yrs or less bc of craftsmanship
HAVE A PLAN, research/read research/read research/read until your eye turn bloodshot. The absolute BIGGEST waste of money in this hobby are FAILURES. 1) Buying and killing corals/fish that you should have never bought at the time in the first place....all bc you didn't research what the buying impact would be on your system. 2) Buying cheap equipment that you end up replacing every 2-3 years bc of failures. You buy a well-built well-reviewed pieces of equipment, it should last 5-10+ yrs.
READ R2R FORUMS DURING THE BUILD-PROCESS!!!! Money is wasted a lot during the build process bc of inexperience or things just go sideways on one thing or another. Always research what others have done. Goal here is to dodge bullets by reading ahead of time potential problems before you start various stages of the build.
Stand in other peoples shoulders!
Good luck
.