Advice and suggestions needed

Hello, I'm Joey from the Philippines. I'm a newbie on these things. I really need advice and suggestions on how to progress with my studio construction. I attached the specs via word document, he, he, together with a picture of the finish my wall has. They call it termite finish here, at least that's what i heard. I was wondering if i could retain some portions of that finish coz it might contribute in the diffussion of sound? Just wonderin. Another major concern is that my roof is just GI sheets mounted on wood beams. And the ceiling is just a thin layer of plywood mounted on 2x4's. Ha, ha. I really need advice on how to soundproof it without redoing the roof, for economic reasons. I' m planning to use double gypsum board walls as ceiling. Would that be sufficient or even helpful at all? This studio used to be our living and dinning room. I sealed some windows with CHB. The floor is marble. The concrete wall division was just completed together with the door installation. I'm waiting for the arrival of the people who will install the window and seal the door as im writing this. The space between the structure and the closest neighbor's fence is probably 4-5 meters away. I plan to record a full-band but hopefully it can be a flexible set-up. I dont have a very detailed plan yet. I was hoping this forum would help speed things up on decision making. Your thoughts please. Really need some input here. Any advice will be highly appreciated Thanks for this site. Very encouraging and informative. More power!