Hooking up the wiring to the main box and adding a switch - for that you should hire a licensed electrician, but there's no reason you can't install the post and run the wiring yourself. There's even some added satisfaction for your effort: Your guests will thank you for your hospitality that much more when they can actually see their way to your front door.
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Masonry hoe and wheelbarrow
to cut PVC conduit
Shovel and concrete float
Rope or strapping and stakes
(the fixture that sits atop the post). Lanterns and posts usually sold separately.
These come in only a few styles: fluted, not fluted, with or without a crossbar. It's best to order posts from the same manufacturer as your lantern, to ensure that the finishes match.
You'll need enough UF-rated exterior wire to reach from inside the house to the post outside, plus an extra 9 feet to run up through the post. 12-gauge wire will suit both 15-and 20-amp circuits.
To meet code for burying wires undergorund, you'll need 3/4-inch "Schedule 40" PVC pipe. Get enough elbows and couplings to make any necessary turns coming out of the house, down to the trench, and up to the post from the ground.
5. PVC CEMENT
to adhere the conduit together
6. 3/4-INCH GRAVEL
to fill the bottom 6 inches of the posthole
7. CONCRETE MIX
Two 80-pound sacks should be enough to creat a 12-inch wide and 16-inch-deep footing.
8. WIRE NUTS
to connect the wiring on the lantern. These are color coded by size; yellow should work for 12-gauge wires, but be sure to also check the range of sizes on the packaging.