Building Semi-Pro studio in backyard of residential building

Hello everyone, I have recently purchased property in a residential area which is officially declared as a mixed-use zone. On this land there is an old house which is currently being reconstructed to be used as the future home for my wife and me. This house will also contain an in-law unit and a unit for office space. The grounds are big enough to hold another building and the local building-plan does also allow for this (up to two floors: ground & first). So we would like to build our own studio there. Just to give you a hint about our personal background on what level we are currently working: My wife works as a free-lancer as industrial designer and is also into music (singing, piano & little bit of song-writing). She is somewhere between semi-pro and pro with two different bands and also solo. I'm a software-engineer and had organ-lessons in my youth and I'm now taking some piano-lessons to get my rusty fingers a little into shape. I have started going into home-recording, live-recording and mixing for about 6 years now and would decribe myself being somewhere between dedicated hobbyist and semi-pro. The studio we want to build is primaryly intended for our own purposes: recording the bands of my wife and possibly some other artists/bands close to us. One of the bands of my wife is a jazz-band (piano, upright, drums) the other has just upright & piano. But in the future also things like acoustic & electric guitar & saxophone should be recorded there. It should have a good acoustic & isolation but I'm not aiming for this to be a high-end studio... I thought about a building with one floor of sufficient height (some hints of what you guys deem a sufficient height would be welcome ;-) and about 120 square meters size (about 1300 square feet). I had intended to have the following rooms: Control Room Live Room Vocal Booth Drum Booth Storage Room Bathroom Lounge Do you think that this would fit in the area I projected, or would this leave the individual rooms too small? What would be good sizes for the individual rooms? I'm currently doing a little investigation on how something like this needs to be built. Our timeframe for doing so will probably be in 2-3 years. Our budget for the complete studio (without equipment & instruments) would be between €80k and €100k, we do have quite a few people who know how to lay bricks, do the electrics etc. so quite a bit of the construction work can be done without external help.

Control Room - 30 m2 Live Room - 45 m2 Vocal Booth - 5 m2 Drum Booth - 10 m2 Storage Room - 10 m2 .. you may increase this one and decrease the lounge Bathroom - 2 m2 Lounge - 20 m2 approx 120 sqm something like this would not be bad. We should hire someone to do a project of this dimension to be honest.

Don't forget you'll lose a lot of space to room-within-a-room construction. Here's a 120m2 design I'm looking to start building soon. The sketchup file is available in this thread.

What are the dimensions of the CR and tracking room on that design ? Of course he will loose same space with the walls...