Is this at your residence? For the repair area is it for your stuff only or going to advertise repair also?
This adds alot of overhead (cost, taxes, upkeep, etc). Can one or two crews support the extra expense? Guessing 3 to 4 crews makes the cost managable.
I'm in the same boat as you. Have thought of going enclosed or npr's to keep stuff out of the elements compared to a building. I would say having a large building I would want to have it off my residence and in a retail/commerical setting, adding repair or equipment sales to help offset costs as a long term goal.