One thing service calculations don't take into consideration is occupancy. A single occupant will easily get by using less than a family. In my area we only have to provide calculations for upgrades in the county, the city doesn't require it. The county is ridiculous, I've had a county inspector come to inspect an upgrade that was already approved by the planning dept. load calcs and all and argue that it "had too many 50 amp breakers" for a 200 amp service
He would not pass it till I called his boss, apparently he got a scolding and we weren't on great terms after that.
The county also wants calcs for car chargers but not the city. Incidentally you can set the Tesla HPWC internally to limit it's maximum draw.
