Does this answer your question Lefty?
Smart drive control can reduce the peak current demand way below the sum of all the peak currents. Don't start or stop them all at once, interleave motor on-states, etc. Probably won't cost that much compared to 300 linear actuators, which has got to be north of $10k.
a) external power will be no problem, I know we would need many Amps..
we want o be able at least to go to a certain position, by saying for instance: stay on for 2.1sec,