Reef tanks never correlate with cheap or inexpensive at any point for any size.
I had a 120 setup (wiped out during February Ice storm) and I had close to $8K in that tank with tank, equipment, salt, and LR.
Now I am setting up a 225. Luckily I am able to use the existing equipment I had for the 120 on my 225 since most of it was rated for 250gal. Just need a new system pump ($400) another 250w DE ballast and fixture ($300), LR (aprox 100lbs @$8/lb = $800), and some PVC tubing, fittings ($100)…see cheap!
Oh Gawd…save me from my temptation! Maybe I need rehab!