I have one small cardboard box cut out to hold my plane while starting and two more larger boxes to hold fuel, glow battery, 1/2A starter, Tx, syringe, cleaner, ect. One of those fits inside the other. I can carry the box under one arm and the plane with the other hand. You don't need a power panel, I use the cox battery holder with two D cells.
The #1 most useful item that I have in the box is the homemade 1/2A starter.