Going from my 75 to my 125 costed more than I thought. But I also got a bit better equipment for the 125 than my 75. My logic was and I find it to be very true, spend a little more now and save alot later. If your going to build a new setup why not take your time with it and get some nice equipment? Because in the end you will proboly be more happy with it, and not spend more money to change the stuff you bought first. Hers an exsample. My 125 I could of built my sump and refugium. But instead I got it custom acrilic one build for me. It costed me a bit more but I got SO much more for the money. I got the sump and refugium, I had them add in fluidized canisters for varius media. I had them custom build a protein skimmer for me, and many other little things that will make my life easier. The guy who made it for me has been making htem for over 20 years and they are just perfict. I opted for retro lighting becuase it cheaper, but also because I can mount them into my canopy any way I want. I went with two 250's HQI, and two VHO 110s. With some exsaust fans I put in there heats not really an issue. I built a custom rock support inside my tank to help give support and help rock colapses, That was cheap to make out of pvc piping.
The point im trying to make it take you time and plain everything out. It took me months to get all the equipment I wanted, and to figure out how to make the things to save a bit of money and help out wiht the tank. Its not a race to build a tank, and thouse who usualy rush spend more and wind up not liking what they have. Money is always an issue, but if it takes you a bit longer to get nicer equipment isn't it worth it in the end? After all your looking to have the tank a long time rite? not just a year or two, the move on to something else...
Here is what I have to give you some ideas.
125 Reef ready Clarity plus acrilic tank. The drain bulk head on the tank is a diffrent size. Its 1 and 1/4 inch in diam.
Custom Sump with external refugium, and fulidized canisters, top off system and protein skimmer.
Multi jet spray bars on the return at about 1000GPH, with an additional closed loop circulation at 1000GPH.
Drilled PVC rock support with a hidden power head attached to one end to have some flow over the live rock. (Just did it becuase I find it helps out a bit)
About 180-200 Lbs of live sand, and about 150 Lbs of Live rock. (important to have a bunch of live rock)
Two 250 watt HQI Retro, and 2 110 watt VHO Retro. (exsaust fans in the canopy)
Hope your new setup goes well, and hope this info I have shared helps you out.