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Sizing of sub panels in multi-family dwelling and main service

I'm still in school to become a master electrician and I work with another master electrician. A recent job possibility has both of us a little confused. It is just 2 not as common situations combined together. A house needs to be wired as four units. Two upstairs and 2 downstairs. The general wants everything to be electric, no gas at all. Each unit needing a 12kva furnace, 10kva oven, 5kva dryer, and a hot water heater, 800 sqft. general lighting, laundry circuit, and 2 small appliance. A while back when I figured up a load calc it was right around 130 amps. Now of course all of these can be deducted since there are four units but what about the sizing of the sub-panels and meters? Is it the units need a 150 amp service while the whole building needs a 400 amp service? The boss keeps saying no, the units only need 100 amps because of deductions but I see it as the unit must have its calculated load available to the sub-panel. Where the main service, deductions may take place.

If 150 amps is the answer. Does such a peice exist? A meter assembly with 5 meters (One meter for general hallways) and 150 amp breakers with a 400 amp main?

Thanks for suggestions, it helps me learn planning these things whether they're for one of his jobs or just practice. I just can't seem to find this type of situation in the books.

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