WoW nathan..
not sure weather to say congrats or

.... j/k congrats
well if you are going to think about the in the wall, check to make sure it is or is not a load bearing wall. also braceing for it. that is going ot be a lot of weight for just one with out a sump! my 120 with sump is pushing close to 1300 LBS and that is jusy water...
take a look at
this article here on TRT, i kow you are past most of it but it does have some calucators you might want to use.
since you are thinking of re modeling the house, why not expand the garage a little , if one tank in in the wall, perhaps a smaller fish room in the garrage would be easier.
i think you are going to have a lot of fun with this...
you might want to check with home owners insurance while you are at it.. tanks that big may or may not have an effect on your policy....
as far as your lighting, think about VHO too.. even on the
FOWLR tank, if you have it now .. then when you do decide to go corals your already are there...
ofcourse you need to give us lots of pictures and the lay out of where your tanks are going!
this is going to be a great build thread!!!!!
oh.... since you have some time on your hands before you start the house.. why not make two skimmers now? a total DIY.
so wheressss the picsssssssss