I'm using Sketchup, which is priced right FREE, and find it is incredibly capable allowing awesome detail including among other things a 3 dimensional site pan and excavation plan. There is no manual and the learning process takes a while. If you try it you'll soon need to learn how to use layers, components, and how to print, none of which are intuitive. You'll also want a printer that'll print on bigger paper, I have, and am very pleased with, an HP 7610 that will print on 13" x 19" paper and was quite reasonably priced. I do most of my printing on 8 1/2 x 14 because I can scan them into PDFs that anyone can view. I'll offer to help with the learning by email. Feel free to contact me directly with Sketchup questions
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