Get an extension cord and run it from a point inside your home where you have a plug, I've used 16 gauge 50 ft and 100ft with a Griots, Flex, Rupes 21, and Rupes Mini with no issues.
I'd get the Griots if your only doing your own vehicles, it has a better warranty then the PC, also more correction power. You can also get a 3.5" backing plate and use 4" pads for tighter areas.
Lake Country Hydrotech 4" pads work great on the Griots with 3.5" backing plate.
http://www.autopia-carcare.com/griot...l#.VzI_A7vmqP9
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Roto-Fab intake, SW 1 7/8" LT w/hi flow cats, Flowmaster outlaw exhaust, UDP, 160* stat, Circle D 3200, Moroso catch can, TCI line lock, Zex Nitrous 125 shot, 3.91 gear, Eaton True-trac, DSS 1000hp axles.