Mate, I've seen a few posts from you recently regarding tank sizes etc. As a lot of the posts say, either start with the tank you want and then work out a stocking list OR get the tank you need for the stock list you want...
Given your original stock list I honestly wouldn't put that lot together in anything under 5000 litres. I have 1200 litres in just over 8 feet of tank and the only fish in your list I have is the maroon clowns.. . My biggest fish is an orange shoulder tang... I have considered a vlamingi but don't think I have the room.
Think about it this way... how big a slice of the reef would you need to take to pick up enough natural habitat for all those fish? You're talking millions of gallons... so why squeeze them into less than 0.1% of that?
I'm not trying to bring you down, but unless you're gonna make your living room water tight, you need to be realistic and fair to the fish you wanna keep.
Having said that, a 750xxl isn't big enough for the puffers you clearly love... go custom, you can get what you want and cheaper than off the shelf...
Get a couple of quotes, it'll cost you nothing and you'll see the difference in price.
For reference, mine cost £900 4 years ago, that included tank, drilling, weirs and sump.
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