Mike:
600 amp, single phase is 'normal' on the BIG >10k Sq Ft McMansions here; 800 for 17k Sq ft may be overkill, may not.

Depending on the toys; pool; sauna; jacuzzi's, steamers, etc. the 5 to 10k sq ft range from 300 to 400 amps

One EC has a 21k sq ft maxi-McMansion coming soon....800 amp, 3 phase, 4 wire, 120/208 volt.

Now....don't ask about the bills...or the actual loads! LOL


John