Converting Church In Austin Tx

hello i am in contract to purchase an old church in austin tx with the intention of converting it to a studio and living space. the budget depends on what the bank will loan me as a construction loan, but there are so many things needing doing that cost is definitely an issue. the building is one big room roughly 60' x 30' (1740 sq ft) and needs quite a bit of work to be brought up to city code...... amongst other things it need new foundation (pier and beam) new roof (trusses, decking and all) all electrical and plumbing. i've been getting bids from several contractors and tradesmen, and am now at the stage of getting an architect to draw up plans. i would love to make this work, but have to be realistic about this and i have the next week before my option period is up to figure if this will be financially possible. there are neighbors on either side which is a drag, but i don't plan on having bands in there constantly. i figure if i only track drums during the day i'll be ok. the reality is i spend most of my time solo or working with one other person, but it is good to be able to record in a big room when i want to. there are very few suitable string rooms in town and i think this room could work nicely for that, amongst other things. i would like to keep it as one big open space but in one corner build a self-contained control room as a room within a room with floating floor, etc etc so i can work as late and as loud as possible. i am still looking at various designs for this but am confident i can follow the plans out there properly and have a relatively sound-proof room. i need help trying to make the rest of the place somewhat workable. i have set up studios in several different locations over the past few years, involving various degrees of construction, but none of the projects were as big as this. i have f. alton everests book and rods new one. i read the several web boards about acoustics and construction. although no expert i have spent a lot of time studying the theory and living the reality in the spaces i have been in. so i'm going to ask all of your advice on some of the big issues i'm facing. i'll try and prioritise them so if anyone could even answer 1 or 2 of them i would be most grateful. i only have this week before my option period for the purchase ends so please chime in! 1. there are 9 new somewhat cheap aluminum windows along the 60' walls that pose perhaps the biggest potential for sound loss (remember there are neighbors on both sides). my plan is to rip off the drywall that is there, caulk extensively, pack it with insulation and then build another wall 2" inside, following the 2-leaf model that is in rod's book. i plan on putting similar new windows in this new wall matching up with the windows on the exterior wall. so if someone wants to open a window they will simply have to open two, one after another, one on each wall. is this the best solution? 2. the engineer suggests this new wall be a support wall for the new roof, but he wants to tie it to the old wall somehow. i told him this would compromise the soundproofing so he suggested using metal ties. anyone have a better suggestion? he seems to think it would be necessary to meet code. 2. one of the best things about the space is the old long-leaf pine floors. is there any viable solution to insulate under the floors? some of the contractors suggest several brands of blown-in adhesive cellulose but they are unaware of its stc rating.icynene seems way too expensive and the research i've done here suggests that closed-cell insulation would make the sound loss even worse. any suggestions? 3. finally, my architect is BEGGING me to raise the roof level by 4' and put double clear polycarbonate transom windows all around the church at the top of the walls . he insists this would "make" the space and we have to take the roof off anyway. while i agree aesthetically i would worry about the sound escaping. he suggests polycarbonate as 4' x 8' sheets are quite reasonably priced and he has done it several times before. anyone care to comment on this or how i might make it work? thanks in advance. i REALLY want to make this work.