If you're really this serious, hire an architect with industrial design experience. Give him a list of what you want, a survey of the property and plan to spend a lot of time hashing out the details. Then hire him to supervise the construction.
Unless you are familiar with industrial construction, you are in WAY over your head and will regret not having professional design help and an on-site inspector under your payroll looking out for your interests.
Oh, and the General Contractor does not get his final draw until your inspector signs off on the job... PERIOD!
Don't ask me how I know this.
