Well, I am setting up a 230 gallon, it's a bit bigger but a lot of the necessities are the same, or close enough.
Firstly, buy as much used equipment as possible. I have legitimately saved thousands of dollars buying used. Sure, it sometimes needs some work, or might make a little extra noise or something, but at least you have it, and can upgrade down the road.
Some things to look into that you'll need to buy.
Lights. Depending on what your plan is, corals vs fish will greatly change how much lights will cost. At the very least you're looking at two 165w black boxes.
Protein Skimmer. The model and price will vary depending on what you need, but the price will be $300 or more is my guess.
Sump. A tank that size, I would highly recommend a sump setup. You can either buy a prefab or build your own out of an old tank. That hugely changes the price, a DIY might be $150, a prefab $400+. Again, varying depending on make and model.
Return pump, only necessary if you go Sump, but that's another expense, and opportunity to buy used. Couple hundred bucks, easy.
Plumbing. I just dropped $150CAD on PVC and I still need a few more pieces.
Sand. Even going with a 1" sand bed, that is still 60+lbs of sand, cost varying again. I paid $145 for 80lbs of Carib Sea Hawaiian Black.
Rock. I would personally recommend reusing the rock from your current sand to kick start the cycle, unless you have plans for it. Then go primarily dry rock for the rest to keep the price down. You'll have the ugly stages all over again, but could snag some savings.
Lets not forget powerheads, the number and power will depend on the tank inhabitants, and the quality of pumps. My two Jaebos were $110 each.
Heaters/chillers. Will depend on your climate, but I had to drop $200 on two 400w titanium heaters. (Yay Canada!)
Then there's the recurring costs of water changes. Even a 10% weekly is 15 gallons a week. Adds up to several buckets/boxes of salt a year.
All in all, it's a daunting task, with a hefty price tag, but you know what, you won't regret it. Even if you have to sell a kidney to get there.