Next is power connection. The easiest for both AC and DC use is a Bridge rectifier that I make with four 1N4001 Diodes. You can use smaller diodesBut you ca also use it to power more than one post. I am planning on three.
You can get a full wave bridge rectifier already wired (saves all of that wiring and soldering) for as little as $0.50 each. Add a capacitor and it becomes a constant lighting unit which will work on either A.C. or D.C..
I put several together and the total was less than $1.00 each.