200 feet at 18" can be dug in just a couple hours, depending on the site. If it's a straight shot, it'll be an easy dig. I could do the job in a day myself very easily, 200 feet is only 20 sticks. Easiest way to handle that amount of conduit is to connect it above ground and just roll it into ditch every 3-4 sticks that you connect. Conduit is easy, no real need to worry about rocks but I will make sure the big stuff doesn't come crashing down on the line. Some guys charge by the foot, but out here the rock can be so varied that you could really lose your bottom line pretty quick charging by the foot.