Rear harness will probably run around $60. Plugs into the firewall, runs down the frame. One side goes passenger, one driver and then the license plate light. Probably a 20 min install.
May be cheaper than the electric shop and really not hard to do. I use American Autowire for all my harnesses.
Link:
http://www.americanautowire.com/shop...t-harness-2053