The general rule for boxes is: If there's more than 360° of bends in the run, then a pull-box is required at each 360° point (this is for conduit runs), then the 360° rule starts again 'til you get to the motor. The idea is to not apply too much pressure on the jacket/insulation as you pull the cable through the conduit...therefore the term "pullbox" -
Example:
...... __
......│_│———┐ 90°
.................. │
........ ┌———┘ 90°
........ │ 90°
........ │
........ │
........ │ 90° .... __
........ └————│_│
Now, if you're going to run Romex out of the breaker-panel, then at the location, a stub of conduit down to the motor...you might want to check with your local codes to see if that's permissible...I'm guessing it might not be, but I've seen some PRETTY lax codes in the sticks...
Good luck and don't burn down anything worth your life...
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