Honestly, it is really easy to wire your coop. I am an old lady and I did it. You buy underground wiring, and I only dug my little trench about 6 or 8 inches deep. I did not use conduit. Remember it is a very small trench (narrow, as in narrow wire) to dig, and easy. I have rocky and clay soil, and it was easy. I had to go over 100 feet, and am very glad I have electicity there for winter water. It is not expensive. Extension cords will cost more, IMO.
I was not on BYC last winter, but have heard of numerous stories of coops buring down and all chickens dead.
Whatever you decide to do .... Be safe, Have fun, and Good Luck!
Best wishes, Kathy