I'm in a bit of a quandary here and I was hoping to get some advice. I'm building a new detached garage for my Tesla. The plans (approved by the building department and the power company) call for a sub-panel in the garage. The house has 200 amp service with a 200 amp breaker panel. I figure my maximum electrical use if everything (hot tub, electric dryer, Tesla charging plus other misc use) is turned on at once is 20kW (80 amps). (Hot water and heat are natural gas.) Garage is to the point where we call in the electrician. He says no way he can put a sub-panel in the garage since I already have a 200 amp panel in the house. Says I have to have 400 amp service. Consult the electric company about 400 amp service. They say I have to buy a new transformer ($7000) plus underground wiring to get 400 amp service. I should note that my current electric feed comes from a power pole mounted 25 kW transformer which also feeds 6 other houses plus an ATT DSLAM... seems a bit dodgy. Do I need 400 amp service? Can I put a sub-panel in the garage on my current 200 amp service?