I had two dedicated lines installed a few weeks ago. Here are some things you can do in advance to save the electrician some time (and you some $$):
1) Know exactly where you want the new outlet to be located. Go into your attic and find the spot exactly above the place where the receptacle will be located. In my case I was able to measure from the center of the fireplace in the room, then from the center of the chimney in the attic. I drilled a half inch hole at the spot and dropped a lead line down into the wall. Then I went down to the room, cut a small hole in the drywall, and fished out the line. This could have taken the electrician some time because he's not as familiar with your house as you are. Also, eyeball where you will want the cable to run in the attic. I ran mine along a rafter away from any other wires, and searated from each other by a couple of inches.
2) Check your breaker box to be sure there are some blank spots that can be knocked out. I had three half-inch blanks, so I went to Home Depot and bought two half inch 20A breakers. If there are no blanks he will have to install a secondary breaker box.
3) You'll need two 20A receptacles. Get the kind that permits the installer to insert the bare wire then tighten down on a screw to secure it. They cost a few dollars more, but you get a much better grip on the wire than the kind where the wire is just pushed in.
4) Get an "old work" duplex box, a cover plate, and some large wire staples to secure the wire in the attic. With "old work" boxes a hole is cut in the wall, then the electrician pushes the box in and turns two screws that move some plastic arms against the inside of the drywall to hold it in place. With some of the upgrade outlets like the Oayide I installed you could conceivably pull the box out of the drywall instead of pulling the plug out of the receptacle. I placed the box adjacent to a stud and had the installer drill a screw with a washer through the side of the receptacle box and into the stud.
5) Your electrician doesn't carry 10ga Romex, so be sure he knows that's what you want. It's about $97 for a 125' roll at Home Depot. Remember, the wire can't be cut between the breaker box and the receptacle, so if you're getting it yourself be sure to get enough. I got a 1,000 ft roll from an electrical supply house for $325, and several other members of my audio club will be using it to install their dedicated lines.
Hope this helps.
